summaryrefslogtreecommitdiffstats
path: root/generic/tclEnsemble.c
blob: 986b7c118ffdf3763d99460d61afdc1aa8b1a618 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
/*
 * tclEnsemble.c --
 *
 *	Contains support for ensembles (see TIP#112), which provide simple
 *	mechanism for creating composite commands on top of namespaces.
 *
 * Copyright (c) 2005-2013 Donal K. Fellows.
 *
 * See the file "license.terms" for information on usage and redistribution of
 * this file, and for a DISCLAIMER OF ALL WARRANTIES.
 */

#include "tclInt.h"
#include "tclCompile.h"

/*
 * Declarations for functions local to this file:
 */

static inline Tcl_Obj *	NewNsObj(Tcl_Namespace *namespacePtr);
static inline int	EnsembleUnknownCallback(Tcl_Interp *interp,
			    EnsembleConfig *ensemblePtr, int objc,
			    Tcl_Obj *const objv[], Tcl_Obj **prefixObjPtr);
static int		NsEnsembleImplementationCmd(ClientData clientData,
			    Tcl_Interp *interp,int objc,Tcl_Obj *const objv[]);
static int		NsEnsembleImplementationCmdNR(ClientData clientData,
			    Tcl_Interp *interp,int objc,Tcl_Obj *const objv[]);
static void		BuildEnsembleConfig(EnsembleConfig *ensemblePtr);
static int		NsEnsembleStringOrder(const void *strPtr1,
			    const void *strPtr2);
static void		DeleteEnsembleConfig(ClientData clientData);
static void		MakeCachedEnsembleCommand(Tcl_Obj *objPtr,
			    EnsembleConfig *ensemblePtr, Tcl_HashEntry *hPtr);
static void		FreeEnsembleCmdRep(Tcl_Obj *objPtr);
static void		DupEnsembleCmdRep(Tcl_Obj *objPtr, Tcl_Obj *copyPtr);
static void		CompileToInvokedCommand(Tcl_Interp *interp,
			    Tcl_Parse *parsePtr, Tcl_Obj *replacements,
			    Command *cmdPtr, CompileEnv *envPtr);
static int		CompileBasicNArgCommand(Tcl_Interp *interp,
			    Tcl_Parse *parsePtr, Command *cmdPtr,
			    CompileEnv *envPtr);

/*
 * The lists of subcommands and options for the [namespace ensemble] command.
 */

static const char *const ensembleSubcommands[] = {
    "configure", "create", "exists", NULL
};
enum EnsSubcmds {
    ENS_CONFIG, ENS_CREATE, ENS_EXISTS
};

static const char *const ensembleCreateOptions[] = {
    "-command", "-map", "-parameters", "-prefixes", "-subcommands",
    "-unknown", NULL
};
enum EnsCreateOpts {
    CRT_CMD, CRT_MAP, CRT_PARAM, CRT_PREFIX, CRT_SUBCMDS, CRT_UNKNOWN
};

static const char *const ensembleConfigOptions[] = {
    "-map", "-namespace", "-parameters", "-prefixes", "-subcommands",
    "-unknown", NULL
};
enum EnsConfigOpts {
    CONF_MAP, CONF_NAMESPACE, CONF_PARAM, CONF_PREFIX, CONF_SUBCMDS,
    CONF_UNKNOWN
};

/*
 * This structure defines a Tcl object type that contains a reference to an
 * ensemble subcommand (e.g. the "length" in [string length ab]). It is used
 * to cache the mapping between the subcommand itself and the real command
 * that implements it.
 */

const Tcl_ObjType tclEnsembleCmdType = {
    "ensembleCommand",		/* the type's name */
    FreeEnsembleCmdRep,		/* freeIntRepProc */
    DupEnsembleCmdRep,		/* dupIntRepProc */
    NULL,			/* updateStringProc */
    NULL			/* setFromAnyProc */
};


static inline Tcl_Obj *
NewNsObj(
    Tcl_Namespace *namespacePtr)
{
    register Namespace *nsPtr = (Namespace *) namespacePtr;

    if (namespacePtr == TclGetGlobalNamespace(nsPtr->interp)) {
	return Tcl_NewStringObj("::", 2);
    } else {
	return Tcl_NewStringObj(nsPtr->fullName, -1);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * TclNamespaceEnsembleCmd --
 *
 *	Invoked to implement the "namespace ensemble" command that creates and
 *	manipulates ensembles built on top of namespaces. Handles the
 *	following syntax:
 *
 *	    namespace ensemble name ?dictionary?
 *
 * Results:
 *	Returns TCL_OK if successful, and TCL_ERROR if anything goes wrong.
 *
 * Side effects:
 *	Creates the ensemble for the namespace if one did not previously
 *	exist. Alternatively, alters the way that the ensemble's subcommand =>
 *	implementation prefix is configured.
 *
 *----------------------------------------------------------------------
 */

int
TclNamespaceEnsembleCmd(
    ClientData dummy,
    Tcl_Interp *interp,
    int objc,
    Tcl_Obj *const objv[])
{
    Tcl_Namespace *namespacePtr;
    Namespace *nsPtr = (Namespace *) TclGetCurrentNamespace(interp);
    Tcl_Command token;
    Tcl_DictSearch search;
    Tcl_Obj *listObj;
    int index, done;

    if (nsPtr == NULL || nsPtr->flags & NS_DYING) {
	if (!Tcl_InterpDeleted(interp)) {
	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
		    "tried to manipulate ensemble of deleted namespace",
		    -1));
	    Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE", "DEAD", NULL);
	}
	return TCL_ERROR;
    }

    if (objc < 2) {
	Tcl_WrongNumArgs(interp, 1, objv, "subcommand ?arg ...?");
	return TCL_ERROR;
    }
    if (Tcl_GetIndexFromObj(interp, objv[1], ensembleSubcommands,
	    "subcommand", 0, &index) != TCL_OK) {
	return TCL_ERROR;
    }

    switch ((enum EnsSubcmds) index) {
    case ENS_CREATE: {
	const char *name;
	int len, allocatedMapFlag = 0;
	/*
	 * Defaults
	 */
	Tcl_Obj *subcmdObj = NULL;
	Tcl_Obj *mapObj = NULL;
	int permitPrefix = 1;
	Tcl_Obj *unknownObj = NULL;
	Tcl_Obj *paramObj = NULL;

	/*
	 * Check that we've got option-value pairs... [Bug 1558654]
	 */

	if (objc & 1) {
	    Tcl_WrongNumArgs(interp, 2, objv, "?option value ...?");
	    return TCL_ERROR;
	}
	objv += 2;
	objc -= 2;

	/*
	 * Work out what name to use for the command to create. If supplied,
	 * it is either fully specified or relative to the current namespace.
	 * If not supplied, it is exactly the name of the current namespace.
	 */

	name = nsPtr->fullName;

	/*
	 * Parse the option list, applying type checks as we go. Note that we
	 * are not incrementing any reference counts in the objects at this
	 * stage, so the presence of an option multiple times won't cause any
	 * memory leaks.
	 */

	for (; objc>1 ; objc-=2,objv+=2) {
	    if (Tcl_GetIndexFromObj(interp, objv[0], ensembleCreateOptions,
		    "option", 0, &index) != TCL_OK) {
		if (allocatedMapFlag) {
		    Tcl_DecrRefCount(mapObj);
		}
		return TCL_ERROR;
	    }
	    switch ((enum EnsCreateOpts) index) {
	    case CRT_CMD:
		name = TclGetString(objv[1]);
		continue;
	    case CRT_SUBCMDS:
		if (TclListObjLength(interp, objv[1], &len) != TCL_OK) {
		    if (allocatedMapFlag) {
			Tcl_DecrRefCount(mapObj);
		    }
		    return TCL_ERROR;
		}
		subcmdObj = (len > 0 ? objv[1] : NULL);
		continue;
	    case CRT_PARAM:
		if (TclListObjLength(interp, objv[1], &len) != TCL_OK) {
		    if (allocatedMapFlag) {
			Tcl_DecrRefCount(mapObj);
		    }
		    return TCL_ERROR;
		}
		paramObj = (len > 0 ? objv[1] : NULL);
		continue;
	    case CRT_MAP: {
		Tcl_Obj *patchedDict = NULL, *subcmdWordsObj;

		/*
		 * Verify that the map is sensible.
		 */

		if (Tcl_DictObjFirst(interp, objv[1], &search,
			&subcmdWordsObj, &listObj, &done) != TCL_OK) {
		    if (allocatedMapFlag) {
			Tcl_DecrRefCount(mapObj);
		    }
		    return TCL_ERROR;
		}
		if (done) {
		    mapObj = NULL;
		    continue;
		}
		do {
		    Tcl_Obj **listv;
		    const char *cmd;

		    if (TclListObjGetElements(interp, listObj, &len,
			    &listv) != TCL_OK) {
			Tcl_DictObjDone(&search);
			if (patchedDict) {
			    Tcl_DecrRefCount(patchedDict);
			}
			if (allocatedMapFlag) {
			    Tcl_DecrRefCount(mapObj);
			}
			return TCL_ERROR;
		    }
		    if (len < 1) {
			Tcl_SetObjResult(interp, Tcl_NewStringObj(
				"ensemble subcommand implementations "
				"must be non-empty lists", -1));
			Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE",
				"EMPTY_TARGET", NULL);
			Tcl_DictObjDone(&search);
			if (patchedDict) {
			    Tcl_DecrRefCount(patchedDict);
			}
			if (allocatedMapFlag) {
			    Tcl_DecrRefCount(mapObj);
			}
			return TCL_ERROR;
		    }
		    cmd = TclGetString(listv[0]);
		    if (!(cmd[0] == ':' && cmd[1] == ':')) {
			Tcl_Obj *newList = Tcl_NewListObj(len, listv);
			Tcl_Obj *newCmd = NewNsObj((Tcl_Namespace *) nsPtr);

			if (nsPtr->parentPtr) {
			    Tcl_AppendStringsToObj(newCmd, "::", NULL);
			}
			Tcl_AppendObjToObj(newCmd, listv[0]);
			Tcl_ListObjReplace(NULL, newList, 0, 1, 1, &newCmd);
			if (patchedDict == NULL) {
			    patchedDict = Tcl_DuplicateObj(objv[1]);
			}
			Tcl_DictObjPut(NULL, patchedDict, subcmdWordsObj,
				newList);
		    }
		    Tcl_DictObjNext(&search, &subcmdWordsObj,&listObj, &done);
		} while (!done);

		if (allocatedMapFlag) {
		    Tcl_DecrRefCount(mapObj);
		}
		mapObj = (patchedDict ? patchedDict : objv[1]);
		if (patchedDict) {
		    allocatedMapFlag = 1;
		}
		continue;
	    }
	    case CRT_PREFIX:
		if (Tcl_GetBooleanFromObj(interp, objv[1],
			&permitPrefix) != TCL_OK) {
		    if (allocatedMapFlag) {
			Tcl_DecrRefCount(mapObj);
		    }
		    return TCL_ERROR;
		}
		continue;
	    case CRT_UNKNOWN:
		if (TclListObjLength(interp, objv[1], &len) != TCL_OK) {
		    if (allocatedMapFlag) {
			Tcl_DecrRefCount(mapObj);
		    }
		    return TCL_ERROR;
		}
		unknownObj = (len > 0 ? objv[1] : NULL);
		continue;
	    }
	}

	/*
	 * Create the ensemble. Note that this might delete another ensemble
	 * linked to the same namespace, so we must be careful. However, we
	 * should be OK because we only link the namespace into the list once
	 * we've created it (and after any deletions have occurred.)
	 */

	token = Tcl_CreateEnsemble(interp, name, NULL,
		(permitPrefix ? TCL_ENSEMBLE_PREFIX : 0));
	Tcl_SetEnsembleSubcommandList(interp, token, subcmdObj);
	Tcl_SetEnsembleMappingDict(interp, token, mapObj);
	Tcl_SetEnsembleUnknownHandler(interp, token, unknownObj);
	Tcl_SetEnsembleParameterList(interp, token, paramObj);

	/*
	 * Tricky! Must ensure that the result is not shared (command delete
	 * traces could have corrupted the pristine object that we started
	 * with). [Snit test rename-1.5]
	 */

	Tcl_ResetResult(interp);
	Tcl_GetCommandFullName(interp, token, Tcl_GetObjResult(interp));
	return TCL_OK;
    }

    case ENS_EXISTS:
	if (objc != 3) {
	    Tcl_WrongNumArgs(interp, 2, objv, "cmdname");
	    return TCL_ERROR;
	}
	Tcl_SetObjResult(interp, Tcl_NewBooleanObj(
		Tcl_FindEnsemble(interp, objv[2], 0) != NULL));
	return TCL_OK;

    case ENS_CONFIG:
	if (objc < 3 || (objc != 4 && !(objc & 1))) {
	    Tcl_WrongNumArgs(interp, 2, objv,
		    "cmdname ?-option value ...? ?arg ...?");
	    return TCL_ERROR;
	}
	token = Tcl_FindEnsemble(interp, objv[2], TCL_LEAVE_ERR_MSG);
	if (token == NULL) {
	    return TCL_ERROR;
	}

	if (objc == 4) {
	    Tcl_Obj *resultObj = NULL;		/* silence gcc 4 warning */

	    if (Tcl_GetIndexFromObj(interp, objv[3], ensembleConfigOptions,
		    "option", 0, &index) != TCL_OK) {
		return TCL_ERROR;
	    }
	    switch ((enum EnsConfigOpts) index) {
	    case CONF_SUBCMDS:
		Tcl_GetEnsembleSubcommandList(NULL, token, &resultObj);
		if (resultObj != NULL) {
		    Tcl_SetObjResult(interp, resultObj);
		}
		break;
	    case CONF_PARAM:
		Tcl_GetEnsembleParameterList(NULL, token, &resultObj);
		if (resultObj != NULL) {
		    Tcl_SetObjResult(interp, resultObj);
		}
		break;
	    case CONF_MAP:
		Tcl_GetEnsembleMappingDict(NULL, token, &resultObj);
		if (resultObj != NULL) {
		    Tcl_SetObjResult(interp, resultObj);
		}
		break;
	    case CONF_NAMESPACE:
		namespacePtr = NULL;		/* silence gcc 4 warning */
		Tcl_GetEnsembleNamespace(NULL, token, &namespacePtr);
		Tcl_SetObjResult(interp, NewNsObj(namespacePtr));
		break;
	    case CONF_PREFIX: {
		int flags = 0;			/* silence gcc 4 warning */

		Tcl_GetEnsembleFlags(NULL, token, &flags);
		Tcl_SetObjResult(interp,
			Tcl_NewBooleanObj(flags & TCL_ENSEMBLE_PREFIX));
		break;
	    }
	    case CONF_UNKNOWN:
		Tcl_GetEnsembleUnknownHandler(NULL, token, &resultObj);
		if (resultObj != NULL) {
		    Tcl_SetObjResult(interp, resultObj);
		}
		break;
	    }
	} else if (objc == 3) {
	    /*
	     * Produce list of all information.
	     */

	    Tcl_Obj *resultObj, *tmpObj = NULL;	/* silence gcc 4 warning */
	    int flags = 0;			/* silence gcc 4 warning */

	    TclNewObj(resultObj);

	    /* -map option */
	    Tcl_ListObjAppendElement(NULL, resultObj,
		    Tcl_NewStringObj(ensembleConfigOptions[CONF_MAP], -1));
	    Tcl_GetEnsembleMappingDict(NULL, token, &tmpObj);
	    Tcl_ListObjAppendElement(NULL, resultObj,
		    (tmpObj != NULL) ? tmpObj : Tcl_NewObj());

	    /* -namespace option */
	    Tcl_ListObjAppendElement(NULL, resultObj,
		    Tcl_NewStringObj(ensembleConfigOptions[CONF_NAMESPACE],
			    -1));
	    namespacePtr = NULL;		/* silence gcc 4 warning */
	    Tcl_GetEnsembleNamespace(NULL, token, &namespacePtr);
	    Tcl_ListObjAppendElement(NULL, resultObj, NewNsObj(namespacePtr));

	    /* -parameters option */
	    Tcl_ListObjAppendElement(NULL, resultObj,
		    Tcl_NewStringObj(ensembleConfigOptions[CONF_PARAM], -1));
	    Tcl_GetEnsembleParameterList(NULL, token, &tmpObj);
	    Tcl_ListObjAppendElement(NULL, resultObj,
		    (tmpObj != NULL) ? tmpObj : Tcl_NewObj());

	    /* -prefix option */
	    Tcl_ListObjAppendElement(NULL, resultObj,
		    Tcl_NewStringObj(ensembleConfigOptions[CONF_PREFIX], -1));
	    Tcl_GetEnsembleFlags(NULL, token, &flags);
	    Tcl_ListObjAppendElement(NULL, resultObj,
		    Tcl_NewBooleanObj(flags & TCL_ENSEMBLE_PREFIX));

	    /* -subcommands option */
	    Tcl_ListObjAppendElement(NULL, resultObj,
		    Tcl_NewStringObj(ensembleConfigOptions[CONF_SUBCMDS],-1));
	    Tcl_GetEnsembleSubcommandList(NULL, token, &tmpObj);
	    Tcl_ListObjAppendElement(NULL, resultObj,
		    (tmpObj != NULL) ? tmpObj : Tcl_NewObj());

	    /* -unknown option */
	    Tcl_ListObjAppendElement(NULL, resultObj,
		    Tcl_NewStringObj(ensembleConfigOptions[CONF_UNKNOWN],-1));
	    Tcl_GetEnsembleUnknownHandler(NULL, token, &tmpObj);
	    Tcl_ListObjAppendElement(NULL, resultObj,
		    (tmpObj != NULL) ? tmpObj : Tcl_NewObj());

	    Tcl_SetObjResult(interp, resultObj);
	} else {
	    int len, allocatedMapFlag = 0;
	    Tcl_Obj *subcmdObj = NULL, *mapObj = NULL, *paramObj = NULL,
		    *unknownObj = NULL; /* Defaults, silence gcc 4 warnings */
	    int permitPrefix, flags = 0;	/* silence gcc 4 warning */

	    Tcl_GetEnsembleSubcommandList(NULL, token, &subcmdObj);
	    Tcl_GetEnsembleMappingDict(NULL, token, &mapObj);
	    Tcl_GetEnsembleParameterList(NULL, token, &paramObj);
	    Tcl_GetEnsembleUnknownHandler(NULL, token, &unknownObj);
	    Tcl_GetEnsembleFlags(NULL, token, &flags);
	    permitPrefix = (flags & TCL_ENSEMBLE_PREFIX) != 0;

	    objv += 3;
	    objc -= 3;

	    /*
	     * Parse the option list, applying type checks as we go. Note that
	     * we are not incrementing any reference counts in the objects at
	     * this stage, so the presence of an option multiple times won't
	     * cause any memory leaks.
	     */

	    for (; objc>0 ; objc-=2,objv+=2) {
		if (Tcl_GetIndexFromObj(interp, objv[0],ensembleConfigOptions,
			"option", 0, &index) != TCL_OK) {
		freeMapAndError:
		    if (allocatedMapFlag) {
			Tcl_DecrRefCount(mapObj);
		    }
		    return TCL_ERROR;
		}
		switch ((enum EnsConfigOpts) index) {
		case CONF_SUBCMDS:
		    if (TclListObjLength(interp, objv[1], &len) != TCL_OK) {
			goto freeMapAndError;
		    }
		    subcmdObj = (len > 0 ? objv[1] : NULL);
		    continue;
		case CONF_PARAM:
		    if (TclListObjLength(interp, objv[1], &len) != TCL_OK) {
			goto freeMapAndError;
		    }
		    paramObj = (len > 0 ? objv[1] : NULL);
		    continue;
		case CONF_MAP: {
		    Tcl_Obj *patchedDict = NULL, *subcmdWordsObj, **listv;
		    const char *cmd;

		    /*
		     * Verify that the map is sensible.
		     */

		    if (Tcl_DictObjFirst(interp, objv[1], &search,
			    &subcmdWordsObj, &listObj, &done) != TCL_OK) {
			goto freeMapAndError;
		    }
		    if (done) {
			mapObj = NULL;
			continue;
		    }
		    do {
			if (TclListObjGetElements(interp, listObj, &len,
				&listv) != TCL_OK) {
			    Tcl_DictObjDone(&search);
			    if (patchedDict) {
				Tcl_DecrRefCount(patchedDict);
			    }
			    goto freeMapAndError;
			}
			if (len < 1) {
			    Tcl_SetObjResult(interp, Tcl_NewStringObj(
				    "ensemble subcommand implementations "
				    "must be non-empty lists", -1));
			    Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE",
				    "EMPTY_TARGET", NULL);
			    Tcl_DictObjDone(&search);
			    if (patchedDict) {
				Tcl_DecrRefCount(patchedDict);
			    }
			    goto freeMapAndError;
			}
			cmd = TclGetString(listv[0]);
			if (!(cmd[0] == ':' && cmd[1] == ':')) {
			    Tcl_Obj *newList = Tcl_DuplicateObj(listObj);
			    Tcl_Obj *newCmd = NewNsObj((Tcl_Namespace*)nsPtr);

			    if (nsPtr->parentPtr) {
				Tcl_AppendStringsToObj(newCmd, "::", NULL);
			    }
			    Tcl_AppendObjToObj(newCmd, listv[0]);
			    Tcl_ListObjReplace(NULL, newList, 0,1, 1,&newCmd);
			    if (patchedDict == NULL) {
				patchedDict = Tcl_DuplicateObj(objv[1]);
			    }
			    Tcl_DictObjPut(NULL, patchedDict, subcmdWordsObj,
				    newList);
			}
			Tcl_DictObjNext(&search, &subcmdWordsObj, &listObj,
				&done);
		    } while (!done);
		    if (allocatedMapFlag) {
			Tcl_DecrRefCount(mapObj);
		    }
		    mapObj = (patchedDict ? patchedDict : objv[1]);
		    if (patchedDict) {
			allocatedMapFlag = 1;
		    }
		    continue;
		}
		case CONF_NAMESPACE:
		    Tcl_SetObjResult(interp, Tcl_NewStringObj(
			    "option -namespace is read-only", -1));
		    Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE", "READ_ONLY",
			    NULL);
		    goto freeMapAndError;
		case CONF_PREFIX:
		    if (Tcl_GetBooleanFromObj(interp, objv[1],
			    &permitPrefix) != TCL_OK) {
			goto freeMapAndError;
		    }
		    continue;
		case CONF_UNKNOWN:
		    if (TclListObjLength(interp, objv[1], &len) != TCL_OK) {
			goto freeMapAndError;
		    }
		    unknownObj = (len > 0 ? objv[1] : NULL);
		    continue;
		}
	    }

	    /*
	     * Update the namespace now that we've finished the parsing stage.
	     */

	    flags = (permitPrefix ? flags|TCL_ENSEMBLE_PREFIX
		    : flags&~TCL_ENSEMBLE_PREFIX);
	    Tcl_SetEnsembleSubcommandList(interp, token, subcmdObj);
	    Tcl_SetEnsembleMappingDict(interp, token, mapObj);
	    Tcl_SetEnsembleParameterList(interp, token, paramObj);
	    Tcl_SetEnsembleUnknownHandler(interp, token, unknownObj);
	    Tcl_SetEnsembleFlags(interp, token, flags);
	}
	return TCL_OK;

    default:
	Tcl_Panic("unexpected ensemble command");
    }
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_CreateEnsemble --
 *
 *	Create a simple ensemble attached to the given namespace.
 *
 * Results:
 *	The token for the command created.
 *
 * Side effects:
 *	The ensemble is created and marked for compilation.
 *
 *----------------------------------------------------------------------
 */

Tcl_Command
Tcl_CreateEnsemble(
    Tcl_Interp *interp,
    const char *name,
    Tcl_Namespace *namespacePtr,
    int flags)
{
    Namespace *nsPtr = (Namespace *) namespacePtr;
    EnsembleConfig *ensemblePtr = ckalloc(sizeof(EnsembleConfig));
    Tcl_Obj *nameObj = NULL;

    if (nsPtr == NULL) {
	nsPtr = (Namespace *) TclGetCurrentNamespace(interp);
    }

    /*
     * Make the name of the ensemble into a fully qualified name. This might
     * allocate a temporary object.
     */

    if (!(name[0] == ':' && name[1] == ':')) {
	nameObj = NewNsObj((Tcl_Namespace *) nsPtr);
	if (nsPtr->parentPtr == NULL) {
	    Tcl_AppendStringsToObj(nameObj, name, NULL);
	} else {
	    Tcl_AppendStringsToObj(nameObj, "::", name, NULL);
	}
	Tcl_IncrRefCount(nameObj);
	name = TclGetString(nameObj);
    }

    ensemblePtr->nsPtr = nsPtr;
    ensemblePtr->epoch = 0;
    Tcl_InitHashTable(&ensemblePtr->subcommandTable, TCL_STRING_KEYS);
    ensemblePtr->subcommandArrayPtr = NULL;
    ensemblePtr->subcmdList = NULL;
    ensemblePtr->subcommandDict = NULL;
    ensemblePtr->flags = flags;
    ensemblePtr->numParameters = 0;
    ensemblePtr->parameterList = NULL;
    ensemblePtr->unknownHandler = NULL;
    ensemblePtr->token = Tcl_NRCreateCommand(interp, name,
	    NsEnsembleImplementationCmd, NsEnsembleImplementationCmdNR,
	    ensemblePtr, DeleteEnsembleConfig);
    ensemblePtr->next = (EnsembleConfig *) nsPtr->ensembles;
    nsPtr->ensembles = (Tcl_Ensemble *) ensemblePtr;

    /*
     * Trigger an eventual recomputation of the ensemble command set. Note
     * that this is slightly tricky, as it means that we are not actually
     * counting the number of namespace export actions, but it is the simplest
     * way to go!
     */

    nsPtr->exportLookupEpoch++;

    if (flags & ENSEMBLE_COMPILE) {
	((Command *) ensemblePtr->token)->compileProc = TclCompileEnsemble;
    }

    if (nameObj != NULL) {
	TclDecrRefCount(nameObj);
    }
    return ensemblePtr->token;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_SetEnsembleSubcommandList --
 *
 *	Set the subcommand list for a particular ensemble.
 *
 * Results:
 *	Tcl result code (error if command token does not indicate an ensemble
 *	or the subcommand list - if non-NULL - is not a list).
 *
 * Side effects:
 *	The ensemble is updated and marked for recompilation.
 *
 *----------------------------------------------------------------------
 */

int
Tcl_SetEnsembleSubcommandList(
    Tcl_Interp *interp,
    Tcl_Command token,
    Tcl_Obj *subcmdList)
{
    Command *cmdPtr = (Command *) token;
    EnsembleConfig *ensemblePtr;
    Tcl_Obj *oldList;

    if (cmdPtr->objProc != NsEnsembleImplementationCmd) {
	Tcl_SetObjResult(interp, Tcl_NewStringObj(
		"command is not an ensemble", -1));
	Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE", "NOT_ENSEMBLE", NULL);
	return TCL_ERROR;
    }
    if (subcmdList != NULL) {
	int length;

	if (TclListObjLength(interp, subcmdList, &length) != TCL_OK) {
	    return TCL_ERROR;
	}
	if (length < 1) {
	    subcmdList = NULL;
	}
    }

    ensemblePtr = cmdPtr->objClientData;
    oldList = ensemblePtr->subcmdList;
    ensemblePtr->subcmdList = subcmdList;
    if (subcmdList != NULL) {
	Tcl_IncrRefCount(subcmdList);
    }
    if (oldList != NULL) {
	TclDecrRefCount(oldList);
    }

    /*
     * Trigger an eventual recomputation of the ensemble command set. Note
     * that this is slightly tricky, as it means that we are not actually
     * counting the number of namespace export actions, but it is the simplest
     * way to go!
     */

    ensemblePtr->nsPtr->exportLookupEpoch++;

    /*
     * Special hack to make compiling of [info exists] work when the
     * dictionary is modified.
     */

    if (cmdPtr->compileProc != NULL) {
	((Interp *) interp)->compileEpoch++;
    }

    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_SetEnsembleParameterList --
 *
 *	Set the parameter list for a particular ensemble.
 *
 * Results:
 *	Tcl result code (error if command token does not indicate an ensemble
 *	or the parameter list - if non-NULL - is not a list).
 *
 * Side effects:
 *	The ensemble is updated and marked for recompilation.
 *
 *----------------------------------------------------------------------
 */

int
Tcl_SetEnsembleParameterList(
    Tcl_Interp *interp,
    Tcl_Command token,
    Tcl_Obj *paramList)
{
    Command *cmdPtr = (Command *) token;
    EnsembleConfig *ensemblePtr;
    Tcl_Obj *oldList;
    int length;

    if (cmdPtr->objProc != NsEnsembleImplementationCmd) {
	Tcl_SetObjResult(interp, Tcl_NewStringObj(
		"command is not an ensemble", -1));
	Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE", "NOT_ENSEMBLE", NULL);
	return TCL_ERROR;
    }
    if (paramList == NULL) {
	length = 0;
    } else {
	if (TclListObjLength(interp, paramList, &length) != TCL_OK) {
	    return TCL_ERROR;
	}
	if (length < 1) {
	    paramList = NULL;
	}
    }

    ensemblePtr = cmdPtr->objClientData;
    oldList = ensemblePtr->parameterList;
    ensemblePtr->parameterList = paramList;
    if (paramList != NULL) {
	Tcl_IncrRefCount(paramList);
    }
    if (oldList != NULL) {
	TclDecrRefCount(oldList);
    }
    ensemblePtr->numParameters = length;

    /*
     * Trigger an eventual recomputation of the ensemble command set. Note
     * that this is slightly tricky, as it means that we are not actually
     * counting the number of namespace export actions, but it is the simplest
     * way to go!
     */

    ensemblePtr->nsPtr->exportLookupEpoch++;

    /*
     * Special hack to make compiling of [info exists] work when the
     * dictionary is modified.
     */

    if (cmdPtr->compileProc != NULL) {
	((Interp *) interp)->compileEpoch++;
    }

    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_SetEnsembleMappingDict --
 *
 *	Set the mapping dictionary for a particular ensemble.
 *
 * Results:
 *	Tcl result code (error if command token does not indicate an ensemble
 *	or the mapping - if non-NULL - is not a dict).
 *
 * Side effects:
 *	The ensemble is updated and marked for recompilation.
 *
 *----------------------------------------------------------------------
 */

int
Tcl_SetEnsembleMappingDict(
    Tcl_Interp *interp,
    Tcl_Command token,
    Tcl_Obj *mapDict)
{
    Command *cmdPtr = (Command *) token;
    EnsembleConfig *ensemblePtr;
    Tcl_Obj *oldDict;

    if (cmdPtr->objProc != NsEnsembleImplementationCmd) {
	Tcl_SetObjResult(interp, Tcl_NewStringObj(
		"command is not an ensemble", -1));
	Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE", "NOT_ENSEMBLE", NULL);
	return TCL_ERROR;
    }
    if (mapDict != NULL) {
	int size, done;
	Tcl_DictSearch search;
	Tcl_Obj *valuePtr;

	if (Tcl_DictObjSize(interp, mapDict, &size) != TCL_OK) {
	    return TCL_ERROR;
	}

	for (Tcl_DictObjFirst(NULL, mapDict, &search, NULL, &valuePtr, &done);
		!done; Tcl_DictObjNext(&search, NULL, &valuePtr, &done)) {
	    Tcl_Obj *cmdObjPtr;
	    const char *bytes;

	    if (Tcl_ListObjIndex(interp, valuePtr, 0, &cmdObjPtr) != TCL_OK) {
		Tcl_DictObjDone(&search);
		return TCL_ERROR;
	    }
	    bytes = TclGetString(cmdObjPtr);
	    if (bytes[0] != ':' || bytes[1] != ':') {
		Tcl_SetObjResult(interp, Tcl_NewStringObj(
			"ensemble target is not a fully-qualified command",
			-1));
		Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE",
			"UNQUALIFIED_TARGET", NULL);
		Tcl_DictObjDone(&search);
		return TCL_ERROR;
	    }
	}

	if (size < 1) {
	    mapDict = NULL;
	}
    }

    ensemblePtr = cmdPtr->objClientData;
    oldDict = ensemblePtr->subcommandDict;
    ensemblePtr->subcommandDict = mapDict;
    if (mapDict != NULL) {
	Tcl_IncrRefCount(mapDict);
    }
    if (oldDict != NULL) {
	TclDecrRefCount(oldDict);
    }

    /*
     * Trigger an eventual recomputation of the ensemble command set. Note
     * that this is slightly tricky, as it means that we are not actually
     * counting the number of namespace export actions, but it is the simplest
     * way to go!
     */

    ensemblePtr->nsPtr->exportLookupEpoch++;

    /*
     * Special hack to make compiling of [info exists] work when the
     * dictionary is modified.
     */

    if (cmdPtr->compileProc != NULL) {
	((Interp *) interp)->compileEpoch++;
    }

    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_SetEnsembleUnknownHandler --
 *
 *	Set the unknown handler for a particular ensemble.
 *
 * Results:
 *	Tcl result code (error if command token does not indicate an ensemble
 *	or the unknown handler - if non-NULL - is not a list).
 *
 * Side effects:
 *	The ensemble is updated and marked for recompilation.
 *
 *----------------------------------------------------------------------
 */

int
Tcl_SetEnsembleUnknownHandler(
    Tcl_Interp *interp,
    Tcl_Command token,
    Tcl_Obj *unknownList)
{
    Command *cmdPtr = (Command *) token;
    EnsembleConfig *ensemblePtr;
    Tcl_Obj *oldList;

    if (cmdPtr->objProc != NsEnsembleImplementationCmd) {
	Tcl_SetObjResult(interp, Tcl_NewStringObj(
		"command is not an ensemble", -1));
	Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE", "NOT_ENSEMBLE", NULL);
	return TCL_ERROR;
    }
    if (unknownList != NULL) {
	int length;

	if (TclListObjLength(interp, unknownList, &length) != TCL_OK) {
	    return TCL_ERROR;
	}
	if (length < 1) {
	    unknownList = NULL;
	}
    }

    ensemblePtr = cmdPtr->objClientData;
    oldList = ensemblePtr->unknownHandler;
    ensemblePtr->unknownHandler = unknownList;
    if (unknownList != NULL) {
	Tcl_IncrRefCount(unknownList);
    }
    if (oldList != NULL) {
	TclDecrRefCount(oldList);
    }

    /*
     * Trigger an eventual recomputation of the ensemble command set. Note
     * that this is slightly tricky, as it means that we are not actually
     * counting the number of namespace export actions, but it is the simplest
     * way to go!
     */

    ensemblePtr->nsPtr->exportLookupEpoch++;

    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_SetEnsembleFlags --
 *
 *	Set the flags for a particular ensemble.
 *
 * Results:
 *	Tcl result code (error if command token does not indicate an
 *	ensemble).
 *
 * Side effects:
 *	The ensemble is updated and marked for recompilation.
 *
 *----------------------------------------------------------------------
 */

int
Tcl_SetEnsembleFlags(
    Tcl_Interp *interp,
    Tcl_Command token,
    int flags)
{
    Command *cmdPtr = (Command *) token;
    EnsembleConfig *ensemblePtr;
    int wasCompiled;

    if (cmdPtr->objProc != NsEnsembleImplementationCmd) {
	Tcl_SetObjResult(interp, Tcl_NewStringObj(
		"command is not an ensemble", -1));
	Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE", "NOT_ENSEMBLE", NULL);
	return TCL_ERROR;
    }

    ensemblePtr = cmdPtr->objClientData;
    wasCompiled = ensemblePtr->flags & ENSEMBLE_COMPILE;

    /*
     * This API refuses to set the ENSEMBLE_DEAD flag...
     */

    ensemblePtr->flags &= ENSEMBLE_DEAD;
    ensemblePtr->flags |= flags & ~ENSEMBLE_DEAD;

    /*
     * Trigger an eventual recomputation of the ensemble command set. Note
     * that this is slightly tricky, as it means that we are not actually
     * counting the number of namespace export actions, but it is the simplest
     * way to go!
     */

    ensemblePtr->nsPtr->exportLookupEpoch++;

    /*
     * If the ENSEMBLE_COMPILE flag status was changed, install or remove the
     * compiler function and bump the interpreter's compilation epoch so that
     * bytecode gets regenerated.
     */

    if (flags & ENSEMBLE_COMPILE) {
	if (!wasCompiled) {
	    ((Command*) ensemblePtr->token)->compileProc = TclCompileEnsemble;
	    ((Interp *) interp)->compileEpoch++;
	}
    } else {
	if (wasCompiled) {
	    ((Command *) ensemblePtr->token)->compileProc = NULL;
	    ((Interp *) interp)->compileEpoch++;
	}
    }

    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_GetEnsembleSubcommandList --
 *
 *	Get the list of subcommands associated with a particular ensemble.
 *
 * Results:
 *	Tcl result code (error if command token does not indicate an
 *	ensemble). The list of subcommands is returned by updating the
 *	variable pointed to by the last parameter (NULL if this is to be
 *	derived from the mapping dictionary or the associated namespace's
 *	exported commands).
 *
 * Side effects:
 *	None
 *
 *----------------------------------------------------------------------
 */

int
Tcl_GetEnsembleSubcommandList(
    Tcl_Interp *interp,
    Tcl_Command token,
    Tcl_Obj **subcmdListPtr)
{
    Command *cmdPtr = (Command *) token;
    EnsembleConfig *ensemblePtr;

    if (cmdPtr->objProc != NsEnsembleImplementationCmd) {
	if (interp != NULL) {
	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
		    "command is not an ensemble", -1));
	    Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE", "NOT_ENSEMBLE", NULL);
	}
	return TCL_ERROR;
    }

    ensemblePtr = cmdPtr->objClientData;
    *subcmdListPtr = ensemblePtr->subcmdList;
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_GetEnsembleParameterList --
 *
 *	Get the list of parameters associated with a particular ensemble.
 *
 * Results:
 *	Tcl result code (error if command token does not indicate an
 *	ensemble). The list of parameters is returned by updating the
 *	variable pointed to by the last parameter (NULL if there are
 *	no parameters).
 *
 * Side effects:
 *	None
 *
 *----------------------------------------------------------------------
 */

int
Tcl_GetEnsembleParameterList(
    Tcl_Interp *interp,
    Tcl_Command token,
    Tcl_Obj **paramListPtr)
{
    Command *cmdPtr = (Command *) token;
    EnsembleConfig *ensemblePtr;

    if (cmdPtr->objProc != NsEnsembleImplementationCmd) {
	if (interp != NULL) {
	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
		    "command is not an ensemble", -1));
	    Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE", "NOT_ENSEMBLE", NULL);
	}
	return TCL_ERROR;
    }

    ensemblePtr = cmdPtr->objClientData;
    *paramListPtr = ensemblePtr->parameterList;
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_GetEnsembleMappingDict --
 *
 *	Get the command mapping dictionary associated with a particular
 *	ensemble.
 *
 * Results:
 *	Tcl result code (error if command token does not indicate an
 *	ensemble). The mapping dict is returned by updating the variable
 *	pointed to by the last parameter (NULL if none is installed).
 *
 * Side effects:
 *	None
 *
 *----------------------------------------------------------------------
 */

int
Tcl_GetEnsembleMappingDict(
    Tcl_Interp *interp,
    Tcl_Command token,
    Tcl_Obj **mapDictPtr)
{
    Command *cmdPtr = (Command *) token;
    EnsembleConfig *ensemblePtr;

    if (cmdPtr->objProc != NsEnsembleImplementationCmd) {
	if (interp != NULL) {
	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
		    "command is not an ensemble", -1));
	    Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE", "NOT_ENSEMBLE", NULL);
	}
	return TCL_ERROR;
    }

    ensemblePtr = cmdPtr->objClientData;
    *mapDictPtr = ensemblePtr->subcommandDict;
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_GetEnsembleUnknownHandler --
 *
 *	Get the unknown handler associated with a particular ensemble.
 *
 * Results:
 *	Tcl result code (error if command token does not indicate an
 *	ensemble). The unknown handler is returned by updating the variable
 *	pointed to by the last parameter (NULL if no handler is installed).
 *
 * Side effects:
 *	None
 *
 *----------------------------------------------------------------------
 */

int
Tcl_GetEnsembleUnknownHandler(
    Tcl_Interp *interp,
    Tcl_Command token,
    Tcl_Obj **unknownListPtr)
{
    Command *cmdPtr = (Command *) token;
    EnsembleConfig *ensemblePtr;

    if (cmdPtr->objProc != NsEnsembleImplementationCmd) {
	if (interp != NULL) {
	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
		    "command is not an ensemble", -1));
	    Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE", "NOT_ENSEMBLE", NULL);
	}
	return TCL_ERROR;
    }

    ensemblePtr = cmdPtr->objClientData;
    *unknownListPtr = ensemblePtr->unknownHandler;
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_GetEnsembleFlags --
 *
 *	Get the flags for a particular ensemble.
 *
 * Results:
 *	Tcl result code (error if command token does not indicate an
 *	ensemble). The flags are returned by updating the variable pointed to
 *	by the last parameter.
 *
 * Side effects:
 *	None
 *
 *----------------------------------------------------------------------
 */

int
Tcl_GetEnsembleFlags(
    Tcl_Interp *interp,
    Tcl_Command token,
    int *flagsPtr)
{
    Command *cmdPtr = (Command *) token;
    EnsembleConfig *ensemblePtr;

    if (cmdPtr->objProc != NsEnsembleImplementationCmd) {
	if (interp != NULL) {
	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
		    "command is not an ensemble", -1));
	    Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE", "NOT_ENSEMBLE", NULL);
	}
	return TCL_ERROR;
    }

    ensemblePtr = cmdPtr->objClientData;
    *flagsPtr = ensemblePtr->flags;
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_GetEnsembleNamespace --
 *
 *	Get the namespace associated with a particular ensemble.
 *
 * Results:
 *	Tcl result code (error if command token does not indicate an
 *	ensemble). Namespace is returned by updating the variable pointed to
 *	by the last parameter.
 *
 * Side effects:
 *	None
 *
 *----------------------------------------------------------------------
 */

int
Tcl_GetEnsembleNamespace(
    Tcl_Interp *interp,
    Tcl_Command token,
    Tcl_Namespace **namespacePtrPtr)
{
    Command *cmdPtr = (Command *) token;
    EnsembleConfig *ensemblePtr;

    if (cmdPtr->objProc != NsEnsembleImplementationCmd) {
	if (interp != NULL) {
	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
		    "command is not an ensemble", -1));
	    Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE", "NOT_ENSEMBLE", NULL);
	}
	return TCL_ERROR;
    }

    ensemblePtr = cmdPtr->objClientData;
    *namespacePtrPtr = (Tcl_Namespace *) ensemblePtr->nsPtr;
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_FindEnsemble --
 *
 *	Given a command name, get the ensemble token for it, allowing for
 *	[namespace import]s. [Bug 1017022]
 *
 * Results:
 *	The token for the ensemble command with the given name, or NULL if the
 *	command either does not exist or is not an ensemble (when an error
 *	message will be written into the interp if thats non-NULL).
 *
 * Side effects:
 *	None
 *
 *----------------------------------------------------------------------
 */

Tcl_Command
Tcl_FindEnsemble(
    Tcl_Interp *interp,		/* Where to do the lookup, and where to write
				 * the errors if TCL_LEAVE_ERR_MSG is set in
				 * the flags. */
    Tcl_Obj *cmdNameObj,	/* Name of command to look up. */
    int flags)			/* Either 0 or TCL_LEAVE_ERR_MSG; other flags
				 * are probably not useful. */
{
    Command *cmdPtr;

    cmdPtr = (Command *)
	    Tcl_FindCommand(interp, TclGetString(cmdNameObj), NULL, flags);
    if (cmdPtr == NULL) {
	return NULL;
    }

    if (cmdPtr->objProc != NsEnsembleImplementationCmd) {
	/*
	 * Reuse existing infrastructure for following import link chains
	 * rather than duplicating it.
	 */

	cmdPtr = (Command *) TclGetOriginalCommand((Tcl_Command) cmdPtr);

	if (cmdPtr == NULL || cmdPtr->objProc != NsEnsembleImplementationCmd){
	    if (flags & TCL_LEAVE_ERR_MSG) {
		Tcl_SetObjResult(interp, Tcl_ObjPrintf(
			"\"%s\" is not an ensemble command",
			TclGetString(cmdNameObj)));
		Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "ENSEMBLE",
			TclGetString(cmdNameObj), NULL);
	    }
	    return NULL;
	}
    }

    return (Tcl_Command) cmdPtr;
}

/*
 *----------------------------------------------------------------------
 *
 * Tcl_IsEnsemble --
 *
 *	Simple test for ensemble-hood that takes into account imported
 *	ensemble commands as well.
 *
 * Results:
 *	Boolean value
 *
 * Side effects:
 *	None
 *
 *----------------------------------------------------------------------
 */

int
Tcl_IsEnsemble(
    Tcl_Command token)
{
    Command *cmdPtr = (Command *) token;

    if (cmdPtr->objProc == NsEnsembleImplementationCmd) {
	return 1;
    }
    cmdPtr = (Command *) TclGetOriginalCommand((Tcl_Command) cmdPtr);
    if (cmdPtr == NULL || cmdPtr->objProc != NsEnsembleImplementationCmd) {
	return 0;
    }
    return 1;
}

/*
 *----------------------------------------------------------------------
 *
 * TclMakeEnsemble --
 *
 *	Create an ensemble from a table of implementation commands. The
 *	ensemble will be subject to (limited) compilation if any of the
 *	implementation commands are compilable.
 *
 *	The 'name' parameter may be a single command name or a list if
 *	creating an ensemble subcommand (see the binary implementation).
 *
 *	Currently, the TCL_ENSEMBLE_PREFIX ensemble flag is only used on
 *	top-level ensemble commands.
 *
 * Results:
 *	Handle for the new ensemble, or NULL on failure.
 *
 * Side effects:
 *	May advance the bytecode compilation epoch.
 *
 *----------------------------------------------------------------------
 */

Tcl_Command
TclMakeEnsemble(
    Tcl_Interp *interp,
    const char *name,		 /* The ensemble name (as explained above) */
    const EnsembleImplMap map[]) /* The subcommands to create */
{
    Tcl_Command ensemble;
    Tcl_Namespace *ns;
    Tcl_DString buf, hiddenBuf;
    const char **nameParts = NULL;
    const char *cmdName = NULL;
    int i, nameCount = 0, ensembleFlags = 0, hiddenLen;

    /*
     * Construct the path for the ensemble namespace and create it.
     */

    Tcl_DStringInit(&buf);
    Tcl_DStringInit(&hiddenBuf);
    TclDStringAppendLiteral(&hiddenBuf, "tcl:");
    Tcl_DStringAppend(&hiddenBuf, name, -1);
    TclDStringAppendLiteral(&hiddenBuf, ":");
    hiddenLen = Tcl_DStringLength(&hiddenBuf);
    if (name[0] == ':' && name[1] == ':') {
	/*
	 * An absolute name, so use it directly.
	 */

	cmdName = name;
	Tcl_DStringAppend(&buf, name, -1);
	ensembleFlags = TCL_ENSEMBLE_PREFIX;
    } else {
	/*
	 * Not an absolute name, so do munging of it. Note that this treats a
	 * multi-word list differently to a single word.
	 */

	TclDStringAppendLiteral(&buf, "::tcl");

	if (Tcl_SplitList(NULL, name, &nameCount, &nameParts) != TCL_OK) {
	    Tcl_Panic("invalid ensemble name '%s'", name);
	}

	for (i = 0; i < nameCount; ++i) {
	    TclDStringAppendLiteral(&buf, "::");
	    Tcl_DStringAppend(&buf, nameParts[i], -1);
	}
    }

    ns = Tcl_FindNamespace(interp, Tcl_DStringValue(&buf), NULL,
	    TCL_CREATE_NS_IF_UNKNOWN);
    if (!ns) {
	Tcl_Panic("unable to find or create %s namespace!",
		Tcl_DStringValue(&buf));
    }

    /*
     * Create the named ensemble in the correct namespace
     */

    if (cmdName == NULL) {
	if (nameCount == 1) {
	    ensembleFlags = TCL_ENSEMBLE_PREFIX;
	    cmdName = Tcl_DStringValue(&buf) + 5;
	} else {
	    ns = ns->parentPtr;
	    cmdName = nameParts[nameCount - 1];
	}
    }

    /*
     * Switch on compilation always for core ensembles now that we can do
     * nice bytecode things with them.  Do it now.  Waiting until later will
     * just cause pointless epoch bumps.
     */

    ensembleFlags |= ENSEMBLE_COMPILE;
    ensemble = Tcl_CreateEnsemble(interp, cmdName, ns, ensembleFlags);

    /*
     * Create the ensemble mapping dictionary and the ensemble command procs.
     */

    if (ensemble != NULL) {
	Tcl_Obj *mapDict, *fromObj, *toObj;
	Command *cmdPtr;

	TclDStringAppendLiteral(&buf, "::");
	TclNewObj(mapDict);
	for (i=0 ; map[i].name != NULL ; i++) {
	    fromObj = Tcl_NewStringObj(map[i].name, -1);
	    TclNewStringObj(toObj, Tcl_DStringValue(&buf),
		    Tcl_DStringLength(&buf));
	    Tcl_AppendToObj(toObj, map[i].name, -1);
	    Tcl_DictObjPut(NULL, mapDict, fromObj, toObj);

	    if (map[i].proc || map[i].nreProc) {
		/*
		 * If the command is unsafe, hide it when we're in a safe
		 * interpreter. The code to do this is really hokey! It also
		 * doesn't work properly yet; this function is always
		 * currently called before the safe-interp flag is set so the
		 * Tcl_IsSafe check fails.
		 */

		if (map[i].unsafe && Tcl_IsSafe(interp)) {
		    cmdPtr = (Command *)
			    Tcl_NRCreateCommand(interp, "___tmp", map[i].proc,
			    map[i].nreProc, map[i].clientData, NULL);
		    Tcl_DStringSetLength(&hiddenBuf, hiddenLen);
		    if (Tcl_HideCommand(interp, "___tmp",
			    Tcl_DStringAppend(&hiddenBuf, map[i].name, -1))) {
			Tcl_Panic("%s", Tcl_GetString(Tcl_GetObjResult(interp)));
		    }
		} else {
		    /*
		     * Not hidden, so just create it. Yay!
		     */

		    cmdPtr = (Command *)
			    Tcl_NRCreateCommand(interp, TclGetString(toObj),
			    map[i].proc, map[i].nreProc, map[i].clientData,
			    NULL);
		}
		cmdPtr->compileProc = map[i].compileProc;
	    }
	}
	Tcl_SetEnsembleMappingDict(interp, ensemble, mapDict);
    }

    Tcl_DStringFree(&buf);
    Tcl_DStringFree(&hiddenBuf);
    if (nameParts != NULL) {
	ckfree((char *) nameParts);
    }
    return ensemble;
}

/*
 *----------------------------------------------------------------------
 *
 * NsEnsembleImplementationCmd --
 *
 *	Implements an ensemble of commands (being those exported by a
 *	namespace other than the global namespace) as a command with the same
 *	(short) name as the namespace in the parent namespace.
 *
 * Results:
 *	A standard Tcl result code. Will be TCL_ERROR if the command is not an
 *	unambiguous prefix of any command exported by the ensemble's
 *	namespace.
 *
 * Side effects:
 *	Depends on the command within the namespace that gets executed. If the
 *	ensemble itself returns TCL_ERROR, a descriptive error message will be
 *	placed in the interpreter's result.
 *
 *----------------------------------------------------------------------
 */

static int
NsEnsembleImplementationCmd(
    ClientData clientData,
    Tcl_Interp *interp,
    int objc,
    Tcl_Obj *const objv[])
{
    return Tcl_NRCallObjProc(interp, NsEnsembleImplementationCmdNR,
	    clientData, objc, objv);
}

static int
NsEnsembleImplementationCmdNR(
    ClientData clientData,
    Tcl_Interp *interp,
    int objc,
    Tcl_Obj *const objv[])
{
    EnsembleConfig *ensemblePtr = clientData;
				/* The ensemble itself. */
    Tcl_Obj *prefixObj;		/* An object containing the prefix words of
				 * the command that implements the
				 * subcommand. */
    Tcl_HashEntry *hPtr;	/* Used for efficient lookup of fully
				 * specified but not yet cached command
				 * names. */
    int reparseCount = 0;	/* Number of reparses. */
    Tcl_Obj *errorObj;		/* Used for building error messages. */

    /*
     * Must recheck objc, since numParameters might have changed. Cf. test
     * namespace-53.9.
     */

  restartEnsembleParse:
    if (objc < 2 + ensemblePtr->numParameters) {
	/*
	 * We don't have a subcommand argument. Make error message.
	 */

	Tcl_DString buf;	/* Message being built */
	Tcl_Obj **elemPtrs;	/* Parameter names */
	int len;		/* Number of parameters to append */

	Tcl_DStringInit(&buf);
	if (ensemblePtr->parameterList == NULL) {
	    len = 0;
	} else if (TclListObjGetElements(NULL, ensemblePtr->parameterList,
		&len, &elemPtrs) != TCL_OK) {
	    Tcl_Panic("List of ensemble parameters is not a list");
	}
	for (; len>0; len--,elemPtrs++) {
	    TclDStringAppendObj(&buf, *elemPtrs);
	    TclDStringAppendLiteral(&buf, " ");
	}
	TclDStringAppendLiteral(&buf, "subcommand ?arg ...?");
	Tcl_WrongNumArgs(interp, 1, objv, Tcl_DStringValue(&buf));
	Tcl_DStringFree(&buf);

	return TCL_ERROR;
    }

    if (ensemblePtr->nsPtr->flags & NS_DYING) {
	/*
	 * Don't know how we got here, but make things give up quickly.
	 */

	if (!Tcl_InterpDeleted(interp)) {
	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
		    "ensemble activated for deleted namespace", -1));
	    Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE", "DEAD", NULL);
	}
	return TCL_ERROR;
    }

    /*
     * Determine if the table of subcommands is right. If so, we can just look
     * up in there and go straight to dispatch.
     */

    if (ensemblePtr->epoch == ensemblePtr->nsPtr->exportLookupEpoch) {
	/*
	 * Table of subcommands is still valid; therefore there might be a
	 * valid cache of discovered information which we can reuse. Do the
	 * check here, and if we're still valid, we can jump straight to the
	 * part where we do the invocation of the subcommand.
	 */

	if (objv[1+ensemblePtr->numParameters]->typePtr==&tclEnsembleCmdType){
	    EnsembleCmdRep *ensembleCmd = objv[1+ensemblePtr->numParameters]
		    ->internalRep.twoPtrValue.ptr1;

	    if (ensembleCmd->epoch == ensemblePtr->epoch &&
		    ensembleCmd->token == ensemblePtr->token) {
		prefixObj = Tcl_GetHashValue(ensembleCmd->hPtr);
		Tcl_IncrRefCount(prefixObj);
		goto runResultingSubcommand;
	    }
	}
    } else {
	BuildEnsembleConfig(ensemblePtr);
	ensemblePtr->epoch = ensemblePtr->nsPtr->exportLookupEpoch;
    }

    /*
     * Look in the hashtable for the subcommand name; this is the fastest way
     * of all if there is no cache in operation.
     */

    hPtr = Tcl_FindHashEntry(&ensemblePtr->subcommandTable,
	    TclGetString(objv[1 + ensemblePtr->numParameters]));
    if (hPtr != NULL) {

	/*
	 * Cache for later in the subcommand object.
	 */

	MakeCachedEnsembleCommand(objv[1 + ensemblePtr->numParameters],
		ensemblePtr, hPtr);
    } else if (!(ensemblePtr->flags & TCL_ENSEMBLE_PREFIX)) {
	/*
	 * Could not map, no prefixing, go to unknown/error handling.
	 */

	goto unknownOrAmbiguousSubcommand;
    } else {
	/*
	 * If we've not already confirmed the command with the hash as part of
	 * building our export table, we need to scan the sorted array for
	 * matches.
	 */

	const char *subcmdName; /* Name of the subcommand, or unique prefix of
				 * it (will be an error for a non-unique
				 * prefix). */
	char *fullName = NULL;	/* Full name of the subcommand. */
	int stringLength, i;
	int tableLength = ensemblePtr->subcommandTable.numEntries;

	subcmdName = TclGetString(objv[1 + ensemblePtr->numParameters]);
	stringLength = objv[1 + ensemblePtr->numParameters]->length;
	for (i=0 ; i<tableLength ; i++) {
	    register int cmp = strncmp(subcmdName,
		    ensemblePtr->subcommandArrayPtr[i],
		    (unsigned) stringLength);

	    if (cmp == 0) {
		if (fullName != NULL) {
		    /*
		     * Since there's never the exact-match case to worry about
		     * (hash search filters this), getting here indicates that
		     * our subcommand is an ambiguous prefix of (at least) two
		     * exported subcommands, which is an error case.
		     */

		    goto unknownOrAmbiguousSubcommand;
		}
		fullName = ensemblePtr->subcommandArrayPtr[i];
	    } else if (cmp < 0) {
		/*
		 * Because we are searching a sorted table, we can now stop
		 * searching because we have gone past anything that could
		 * possibly match.
		 */

		break;
	    }
	}
	if (fullName == NULL) {
	    /*
	     * The subcommand is not a prefix of anything, so bail out!
	     */

	    goto unknownOrAmbiguousSubcommand;
	}
	hPtr = Tcl_FindHashEntry(&ensemblePtr->subcommandTable, fullName);
	if (hPtr == NULL) {
	    Tcl_Panic("full name %s not found in supposedly synchronized hash",
		    fullName);
	}

	/*
	 * Cache for later in the subcommand object.
	 */

	MakeCachedEnsembleCommand(objv[1 + ensemblePtr->numParameters],
		ensemblePtr, hPtr);
    }

    prefixObj = Tcl_GetHashValue(hPtr);
    Tcl_IncrRefCount(prefixObj);
  runResultingSubcommand:

    /*
     * Do the real work of execution of the subcommand by building an array of
     * objects (note that this is potentially not the same length as the
     * number of arguments to this ensemble command), populating it and then
     * feeding it back through the main command-lookup engine. In theory, we
     * could look up the command in the namespace ourselves, as we already
     * have the namespace in which it is guaranteed to exist,
     *
     *   ((Q: That's not true if the -map option is used, is it?))
     *
     * but we don't do that (the cacheing of the command object used should
     * help with that.)
     */

    {
	Tcl_Obj **prefixObjv;	/* The list of objects to substitute in as the
				 * target command prefix. */
	Tcl_Obj *copyPtr;	/* The actual list of words to dispatch to.
				 * Will be freed by the dispatch engine. */
	int prefixObjc, copyObjc;
	Interp *iPtr = (Interp *) interp;

	/*
	 * Get the prefix that we're rewriting to. To do this we need to
	 * ensure that the internal representation of the list does not change
	 * so that we can safely keep the internal representations of the
	 * elements in the list.
	 *
	 * TODO: Use conventional list operations to make this code sane!
	 */

	TclListObjGetElements(NULL, prefixObj, &prefixObjc, &prefixObjv);

	copyObjc = objc - 2 + prefixObjc;
	copyPtr = Tcl_NewListObj(copyObjc, NULL);
	if (copyObjc > 0) {
	    register Tcl_Obj **copyObjv;
				/* Space used to construct the list of
				 * arguments to pass to the command that
				 * implements the ensemble subcommand. */
	    register List *listRepPtr = copyPtr->internalRep.twoPtrValue.ptr1;
	    register int i;

	    listRepPtr->elemCount = copyObjc;
	    copyObjv = &listRepPtr->elements;
	    memcpy(copyObjv, prefixObjv, sizeof(Tcl_Obj *) * prefixObjc);
	    memcpy(copyObjv+prefixObjc, objv+1,
		    sizeof(Tcl_Obj *) * ensemblePtr->numParameters);
	    memcpy(copyObjv+prefixObjc+ensemblePtr->numParameters,
		    objv+ensemblePtr->numParameters+2,
		    sizeof(Tcl_Obj *) * (objc-ensemblePtr->numParameters-2));

	    for (i=0; i < copyObjc; i++) {
		Tcl_IncrRefCount(copyObjv[i]);
	    }
	}
	TclDecrRefCount(prefixObj);

	/*
	 * Record what arguments the script sent in so that things like
	 * Tcl_WrongNumArgs can give the correct error message. Parameters
	 * count both as inserted and removed arguments.
	 */

	if (iPtr->ensembleRewrite.sourceObjs == NULL) {
	    iPtr->ensembleRewrite.sourceObjs = objv;
	    iPtr->ensembleRewrite.numRemovedObjs =
		    2 + ensemblePtr->numParameters;
	    iPtr->ensembleRewrite.numInsertedObjs =
		    prefixObjc + ensemblePtr->numParameters;
	    TclNRAddCallback(interp, TclClearRootEnsemble, NULL, NULL, NULL,
		    NULL);
	} else {
	    register int ni = 2 + ensemblePtr->numParameters
		    - iPtr->ensembleRewrite.numInsertedObjs;
				/* Position in objv of new front of insertion
				 * relative to old one. */
	    if (ni > 0) {
		iPtr->ensembleRewrite.numRemovedObjs += ni;
		iPtr->ensembleRewrite.numInsertedObjs += prefixObjc-1;
	    } else {
		iPtr->ensembleRewrite.numInsertedObjs += prefixObjc-2;
	    }
	}

	/*
	 * Hand off to the target command.
	 */

	TclSkipTailcall(interp);
	return TclNREvalObjEx(interp, copyPtr, TCL_EVAL_INVOKE, NULL,INT_MIN);
    }

  unknownOrAmbiguousSubcommand:
    /*
     * Have not been able to match the subcommand asked for with a real
     * subcommand that we export. See whether a handler has been registered
     * for dealing with this situation. Will only call (at most) once for any
     * particular ensemble invocation.
     */

    if (ensemblePtr->unknownHandler != NULL && reparseCount++ < 1) {
	switch (EnsembleUnknownCallback(interp, ensemblePtr, objc, objv,
		&prefixObj)) {
	case TCL_OK:
	    goto runResultingSubcommand;
	case TCL_ERROR:
	    return TCL_ERROR;
	case TCL_CONTINUE:
	    goto restartEnsembleParse;
	}
    }

    /*
     * We cannot determine what subcommand to hand off to, so generate a
     * (standard) failure message. Note the one odd case compared with
     * standard ensemble-like command, which is where a namespace has no
     * exported commands at all...
     */

    Tcl_ResetResult(interp);
    Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "SUBCOMMAND",
	    TclGetString(objv[1+ensemblePtr->numParameters]), NULL);
    if (ensemblePtr->subcommandTable.numEntries == 0) {
	Tcl_SetObjResult(interp, Tcl_ObjPrintf(
		"unknown subcommand \"%s\": namespace %s does not"
		" export any commands",
		TclGetString(objv[1+ensemblePtr->numParameters]),
		ensemblePtr->nsPtr->fullName));
	Tcl_SetErrorCode(interp, "TCL", "LOOKUP", "SUBCOMMAND",
		TclGetString(objv[1+ensemblePtr->numParameters]), NULL);
	return TCL_ERROR;
    }
    errorObj = Tcl_ObjPrintf("unknown%s subcommand \"%s\": must be ",
	    (ensemblePtr->flags & TCL_ENSEMBLE_PREFIX ? " or ambiguous" : ""),
	    TclGetString(objv[1+ensemblePtr->numParameters]));
    if (ensemblePtr->subcommandTable.numEntries == 1) {
	Tcl_AppendToObj(errorObj, ensemblePtr->subcommandArrayPtr[0], -1);
    } else {
	int i;

	for (i=0 ; i<ensemblePtr->subcommandTable.numEntries-1 ; i++) {
	    Tcl_AppendToObj(errorObj, ensemblePtr->subcommandArrayPtr[i], -1);
	    Tcl_AppendToObj(errorObj, ", ", 2);
	}
	Tcl_AppendPrintfToObj(errorObj, "or %s",
		ensemblePtr->subcommandArrayPtr[i]);
    }
    Tcl_SetObjResult(interp, errorObj);
    return TCL_ERROR;
}

int
TclClearRootEnsemble(
    ClientData data[],
    Tcl_Interp *interp,
    int result)
{
    TclResetRewriteEnsemble(interp, 1);
    return result;
}

/*
 *----------------------------------------------------------------------
 *
 * TclInitRewriteEnsemble --
 *
 *	Applies a rewrite of arguments so that an ensemble subcommand will
 *	report error messages correctly for the overall command.
 *
 * Results:
 *	Whether this is the first rewrite applied, a value which must be
 *	passed to TclResetRewriteEnsemble when undoing this command's
 *	behaviour.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

int
TclInitRewriteEnsemble(
    Tcl_Interp *interp,
    int numRemoved,
    int numInserted,
    Tcl_Obj *const *objv)
{
    Interp *iPtr = (Interp *) interp;

    int isRootEnsemble = (iPtr->ensembleRewrite.sourceObjs == NULL);

    if (isRootEnsemble) {
	iPtr->ensembleRewrite.sourceObjs = objv;
	iPtr->ensembleRewrite.numRemovedObjs = numRemoved;
	iPtr->ensembleRewrite.numInsertedObjs = numInserted;
    } else {
	int numIns = iPtr->ensembleRewrite.numInsertedObjs;

	if (numIns < numRemoved) {
	    iPtr->ensembleRewrite.numRemovedObjs += numRemoved - numIns;
	    iPtr->ensembleRewrite.numInsertedObjs += numInserted - 1;
	} else {
	    iPtr->ensembleRewrite.numInsertedObjs += numInserted - numRemoved;
	}
    }
    return isRootEnsemble;
}

/*
 *----------------------------------------------------------------------
 *
 * TclResetRewriteEnsemble --
 *
 *	Removes any rewrites applied to support proper reporting of error
 *	messages used in ensembles. Should be paired with
 *	TclInitRewriteEnsemble.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

void
TclResetRewriteEnsemble(
    Tcl_Interp *interp,
    int isRootEnsemble)
{
    Interp *iPtr = (Interp *) interp;

    if (isRootEnsemble) {
	iPtr->ensembleRewrite.sourceObjs = NULL;
	iPtr->ensembleRewrite.numRemovedObjs = 0;
	iPtr->ensembleRewrite.numInsertedObjs = 0;
    }
}

/*
 * ----------------------------------------------------------------------
 *
 * EnsmebleUnknownCallback --
 *
 *	Helper for the ensemble engine that handles the procesing of unknown
 *	callbacks. See the user documentation of the ensemble unknown handler
 *	for details; this function is only ever called when such a function is
 *	defined, and is only ever called once per ensemble dispatch (i.e. if a
 *	reparse still fails, this isn't called again).
 *
 * Results:
 *	TCL_OK -	*prefixObjPtr contains the command words to dispatch
 *			to.
 *	TCL_CONTINUE -	Need to reparse (*prefixObjPtr is invalid).
 *	TCL_ERROR -	Something went wrong! Error message in interpreter.
 *
 * Side effects:
 *	Calls the Tcl interpreter, so arbitrary.
 *
 * ----------------------------------------------------------------------
 */

static inline int
EnsembleUnknownCallback(
    Tcl_Interp *interp,
    EnsembleConfig *ensemblePtr,
    int objc,
    Tcl_Obj *const objv[],
    Tcl_Obj **prefixObjPtr)
{
    int paramc, i, result, prefixObjc;
    Tcl_Obj **paramv, *unknownCmd, *ensObj;

    /*
     * Create the unknown command callback to determine what to do.
     */

    unknownCmd = Tcl_DuplicateObj(ensemblePtr->unknownHandler);
    TclNewObj(ensObj);
    Tcl_GetCommandFullName(interp, ensemblePtr->token, ensObj);
    Tcl_ListObjAppendElement(NULL, unknownCmd, ensObj);
    for (i=1 ; i<objc ; i++) {
	Tcl_ListObjAppendElement(NULL, unknownCmd, objv[i]);
    }
    TclListObjGetElements(NULL, unknownCmd, &paramc, &paramv);
    Tcl_IncrRefCount(unknownCmd);

    /*
     * Now call the unknown handler. (We don't bother NRE-enabling this; deep
     * recursing through unknown handlers is horribly perverse.) Note that it
     * is always an error for an unknown handler to delete its ensemble; don't
     * do that!
     */

    Tcl_Preserve(ensemblePtr);
    TclSkipTailcall(interp);
    result = Tcl_EvalObjv(interp, paramc, paramv, 0);
    if ((result == TCL_OK) && (ensemblePtr->flags & ENSEMBLE_DEAD)) {
	if (!Tcl_InterpDeleted(interp)) {
	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
		    "unknown subcommand handler deleted its ensemble", -1));
	    Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE", "UNKNOWN_DELETED",
		    NULL);
	}
	result = TCL_ERROR;
    }
    Tcl_Release(ensemblePtr);

    /*
     * If we succeeded, we should either have a list of words that form the
     * command to be executed, or an empty list. In the empty-list case, the
     * ensemble is believed to be updated so we should ask the ensemble engine
     * to reparse the original command.
     */

    if (result == TCL_OK) {
	*prefixObjPtr = Tcl_GetObjResult(interp);
	Tcl_IncrRefCount(*prefixObjPtr);
	TclDecrRefCount(unknownCmd);
	Tcl_ResetResult(interp);

	/*
	 * Namespace is still there. Check if the result is a valid list. If
	 * it is, and it is non-empty, that list is what we are using as our
	 * replacement.
	 */

	if (TclListObjLength(interp, *prefixObjPtr, &prefixObjc) != TCL_OK) {
	    TclDecrRefCount(*prefixObjPtr);
	    Tcl_AddErrorInfo(interp, "\n    while parsing result of "
		    "ensemble unknown subcommand handler");
	    return TCL_ERROR;
	}
	if (prefixObjc > 0) {
	    return TCL_OK;
	}

	/*
	 * Namespace alive & empty result => reparse.
	 */

	TclDecrRefCount(*prefixObjPtr);
	return TCL_CONTINUE;
    }

    /*
     * Oh no! An exceptional result. Convert to an error.
     */

    if (!Tcl_InterpDeleted(interp)) {
	if (result != TCL_ERROR) {
	    Tcl_ResetResult(interp);
	    Tcl_SetObjResult(interp, Tcl_NewStringObj(
		    "unknown subcommand handler returned bad code: ", -1));
	    switch (result) {
	    case TCL_RETURN:
		Tcl_AppendToObj(Tcl_GetObjResult(interp), "return", -1);
		break;
	    case TCL_BREAK:
		Tcl_AppendToObj(Tcl_GetObjResult(interp), "break", -1);
		break;
	    case TCL_CONTINUE:
		Tcl_AppendToObj(Tcl_GetObjResult(interp), "continue", -1);
		break;
	    default:
		Tcl_AppendPrintfToObj(Tcl_GetObjResult(interp), "%d", result);
	    }
	    Tcl_AddErrorInfo(interp, "\n    result of "
		    "ensemble unknown subcommand handler: ");
	    Tcl_AppendObjToErrorInfo(interp, unknownCmd);
	    Tcl_SetErrorCode(interp, "TCL", "ENSEMBLE", "UNKNOWN_RESULT",
		    NULL);
	} else {
	    Tcl_AddErrorInfo(interp,
		    "\n    (ensemble unknown subcommand handler)");
	}
    }
    TclDecrRefCount(unknownCmd);
    return TCL_ERROR;
}

/*
 *----------------------------------------------------------------------
 *
 * MakeCachedEnsembleCommand --
 *
 *	Cache what we've computed so far; it's not nice to repeatedly copy
 *	strings about. Note that to do this, we start by deleting any old
 *	representation that there was (though if it was an out of date
 *	ensemble rep, we can skip some of the deallocation process.)
 *
 * Results:
 *	None
 *
 * Side effects:
 *	Alters the internal representation of the first object parameter.
 *
 *----------------------------------------------------------------------
 */

static void
MakeCachedEnsembleCommand(
    Tcl_Obj *objPtr,
    EnsembleConfig *ensemblePtr,
    Tcl_HashEntry *hPtr)
{
    register EnsembleCmdRep *ensembleCmd;

    if (objPtr->typePtr == &tclEnsembleCmdType) {
	ensembleCmd = objPtr->internalRep.twoPtrValue.ptr1;
    } else {
	/*
	 * Kill the old internal rep, and replace it with a brand new one of
	 * our own.
	 */

	TclFreeIntRep(objPtr);
	ensembleCmd = ckalloc(sizeof(EnsembleCmdRep));
	objPtr->internalRep.twoPtrValue.ptr1 = ensembleCmd;
	objPtr->typePtr = &tclEnsembleCmdType;
    }

    /*
     * Populate the internal rep.
     */

    ensembleCmd->epoch = ensemblePtr->epoch;
    ensembleCmd->token = ensemblePtr->token;
    ensembleCmd->tablePtr = &ensemblePtr->subcommandTable;
    ensembleCmd->hPtr = hPtr;
}

/*
 *----------------------------------------------------------------------
 *
 * DeleteEnsembleConfig --
 *
 *	Destroys the data structure used to represent an ensemble. This is
 *	called when the ensemble's command is deleted (which happens
 *	automatically if the ensemble's namespace is deleted.) Maintainers
 *	should note that ensembles should be deleted by deleting their
 *	commands.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Memory is (eventually) deallocated.
 *
 *----------------------------------------------------------------------
 */

static void
DeleteEnsembleConfig(
    ClientData clientData)
{
    EnsembleConfig *ensemblePtr = clientData;
    Namespace *nsPtr = ensemblePtr->nsPtr;
    Tcl_HashSearch search;
    Tcl_HashEntry *hEnt;

    /*
     * Unlink from the ensemble chain if it has not been marked as having been
     * done already.
     */

    if (ensemblePtr->next != ensemblePtr) {
	EnsembleConfig *ensPtr = (EnsembleConfig *) nsPtr->ensembles;

	if (ensPtr == ensemblePtr) {
	    nsPtr->ensembles = (Tcl_Ensemble *) ensemblePtr->next;
	} else {
	    while (ensPtr != NULL) {
		if (ensPtr->next == ensemblePtr) {
		    ensPtr->next = ensemblePtr->next;
		    break;
		}
		ensPtr = ensPtr->next;
	    }
	}
    }

    /*
     * Mark the namespace as dead so code that uses Tcl_Preserve() can tell
     * whether disaster happened anyway.
     */

    ensemblePtr->flags |= ENSEMBLE_DEAD;

    /*
     * Kill the pointer-containing fields.
     */

    if (ensemblePtr->subcommandTable.numEntries != 0) {
	ckfree(ensemblePtr->subcommandArrayPtr);
    }
    hEnt = Tcl_FirstHashEntry(&ensemblePtr->subcommandTable, &search);
    while (hEnt != NULL) {
	Tcl_Obj *prefixObj = Tcl_GetHashValue(hEnt);

	Tcl_DecrRefCount(prefixObj);
	hEnt = Tcl_NextHashEntry(&search);
    }
    Tcl_DeleteHashTable(&ensemblePtr->subcommandTable);
    if (ensemblePtr->subcmdList != NULL) {
	Tcl_DecrRefCount(ensemblePtr->subcmdList);
    }
    if (ensemblePtr->parameterList != NULL) {
	Tcl_DecrRefCount(ensemblePtr->parameterList);
    }
    if (ensemblePtr->subcommandDict != NULL) {
	Tcl_DecrRefCount(ensemblePtr->subcommandDict);
    }
    if (ensemblePtr->unknownHandler != NULL) {
	Tcl_DecrRefCount(ensemblePtr->unknownHandler);
    }

    /*
     * Arrange for the structure to be reclaimed. Note that this is complex
     * because we have to make sure that we can react sensibly when an
     * ensemble is deleted during the process of initialising the ensemble
     * (especially the unknown callback.)
     */

    Tcl_EventuallyFree(ensemblePtr, TCL_DYNAMIC);
}

/*
 *----------------------------------------------------------------------
 *
 * BuildEnsembleConfig --
 *
 *	Create the internal data structures that describe how an ensemble
 *	looks, being a hash mapping from the full command name to the Tcl list
 *	that describes the implementation prefix words, and a sorted array of
 *	all the full command names to allow for reasonably efficient
 *	unambiguous prefix handling.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Reallocates and rebuilds the hash table and array stored at the
 *	ensemblePtr argument. For large ensembles or large namespaces, this is
 *	a potentially expensive operation.
 *
 *----------------------------------------------------------------------
 */

static void
BuildEnsembleConfig(
    EnsembleConfig *ensemblePtr)
{
    Tcl_HashSearch search;	/* Used for scanning the set of commands in
				 * the namespace that backs up this
				 * ensemble. */
    int i, j, isNew;
    Tcl_HashTable *hash = &ensemblePtr->subcommandTable;
    Tcl_HashEntry *hPtr;

    if (hash->numEntries != 0) {
	/*
	 * Remove pre-existing table.
	 */

	ckfree(ensemblePtr->subcommandArrayPtr);
	hPtr = Tcl_FirstHashEntry(hash, &search);
	while (hPtr != NULL) {
	    Tcl_Obj *prefixObj = Tcl_GetHashValue(hPtr);

	    Tcl_DecrRefCount(prefixObj);
	    hPtr = Tcl_NextHashEntry(&search);
	}
	Tcl_DeleteHashTable(hash);
	Tcl_InitHashTable(hash, TCL_STRING_KEYS);
    }

    /*
     * See if we've got an export list. If so, we will only export exactly
     * those commands, which may be either implemented by the prefix in the
     * subcommandDict or mapped directly onto the namespace's commands.
     */

    if (ensemblePtr->subcmdList != NULL) {
	Tcl_Obj **subcmdv, *target, *cmdObj, *cmdPrefixObj;
	int subcmdc;

	TclListObjGetElements(NULL, ensemblePtr->subcmdList, &subcmdc,
		&subcmdv);
	for (i=0 ; i<subcmdc ; i++) {
	    const char *name = TclGetString(subcmdv[i]);

	    hPtr = Tcl_CreateHashEntry(hash, name, &isNew);

	    /*
	     * Skip non-unique cases.
	     */

	    if (!isNew) {
		continue;
	    }

	    /*
	     * Look in our dictionary (if present) for the command.
	     */

	    if (ensemblePtr->subcommandDict != NULL) {
		Tcl_DictObjGet(NULL, ensemblePtr->subcommandDict, subcmdv[i],
			&target);
		if (target != NULL) {
		    Tcl_SetHashValue(hPtr, target);
		    Tcl_IncrRefCount(target);
		    continue;
		}
	    }

	    /*
	     * Not there, so map onto the namespace. Note in this case that we
	     * do not guarantee that the command is actually there; that is
	     * the programmer's responsibility (or [::unknown] of course).
	     */

	    cmdObj = NewNsObj((Tcl_Namespace *) ensemblePtr->nsPtr);
	    if (ensemblePtr->nsPtr->parentPtr != NULL) {
		Tcl_AppendStringsToObj(cmdObj, "::", name, NULL);
	    } else {
		Tcl_AppendStringsToObj(cmdObj, name, NULL);
	    }
	    cmdPrefixObj = Tcl_NewListObj(1, &cmdObj);
	    Tcl_SetHashValue(hPtr, cmdPrefixObj);
	    Tcl_IncrRefCount(cmdPrefixObj);
	}
    } else if (ensemblePtr->subcommandDict != NULL) {
	/*
	 * No subcmd list, but we do have a mapping dictionary so we should
	 * use the keys of that. Convert the dictionary's contents into the
	 * form required for the ensemble's internal hashtable.
	 */

	Tcl_DictSearch dictSearch;
	Tcl_Obj *keyObj, *valueObj;
	int done;

	Tcl_DictObjFirst(NULL, ensemblePtr->subcommandDict, &dictSearch,
		&keyObj, &valueObj, &done);
	while (!done) {
	    const char *name = TclGetString(keyObj);

	    hPtr = Tcl_CreateHashEntry(hash, name, &isNew);
	    Tcl_SetHashValue(hPtr, valueObj);
	    Tcl_IncrRefCount(valueObj);
	    Tcl_DictObjNext(&dictSearch, &keyObj, &valueObj, &done);
	}
    } else {
	/*
	 * Discover what commands are actually exported by the namespace.
	 * What we have is an array of patterns and a hash table whose keys
	 * are the command names exported by the namespace (the contents do
	 * not matter here.) We must find out what commands are actually
	 * exported by filtering each command in the namespace against each of
	 * the patterns in the export list. Note that we use an intermediate
	 * hash table to make memory management easier, and because that makes
	 * exact matching far easier too.
	 *
	 * Suggestion for future enhancement: compute the unique prefixes and
	 * place them in the hash too, which should make for even faster
	 * matching.
	 */

	hPtr = Tcl_FirstHashEntry(&ensemblePtr->nsPtr->cmdTable, &search);
	for (; hPtr!= NULL ; hPtr=Tcl_NextHashEntry(&search)) {
	    char *nsCmdName =		/* Name of command in namespace. */
		    Tcl_GetHashKey(&ensemblePtr->nsPtr->cmdTable, hPtr);

	    for (i=0 ; i<ensemblePtr->nsPtr->numExportPatterns ; i++) {
		if (Tcl_StringMatch(nsCmdName,
			ensemblePtr->nsPtr->exportArrayPtr[i])) {
		    hPtr = Tcl_CreateHashEntry(hash, nsCmdName, &isNew);

		    /*
		     * Remember, hash entries have a full reference to the
		     * substituted part of the command (as a list) as their
		     * content!
		     */

		    if (isNew) {
			Tcl_Obj *cmdObj, *cmdPrefixObj;

			TclNewObj(cmdObj);
			Tcl_AppendStringsToObj(cmdObj,
				ensemblePtr->nsPtr->fullName,
				(ensemblePtr->nsPtr->parentPtr ? "::" : ""),
				nsCmdName, NULL);
			cmdPrefixObj = Tcl_NewListObj(1, &cmdObj);
			Tcl_SetHashValue(hPtr, cmdPrefixObj);
			Tcl_IncrRefCount(cmdPrefixObj);
		    }
		    break;
		}
	    }
	}
    }

    if (hash->numEntries == 0) {
	ensemblePtr->subcommandArrayPtr = NULL;
	return;
    }

    /*
     * Create a sorted array of all subcommands in the ensemble; hash tables
     * are all very well for a quick look for an exact match, but they can't
     * determine things like whether a string is a prefix of another (not
     * without lots of preparation anyway) and they're no good for when we're
     * generating the error message either.
     *
     * We do this by filling an array with the names (we use the hash keys
     * directly to save a copy, since any time we change the array we change
     * the hash too, and vice versa) and running quicksort over the array.
     */

    ensemblePtr->subcommandArrayPtr =
	    ckalloc(sizeof(char *) * hash->numEntries);

    /*
     * Fill array from both ends as this makes us less likely to end up with
     * performance problems in qsort(), which is good. Note that doing this
     * makes this code much more opaque, but the naive alternatve:
     *
     * for (hPtr=Tcl_FirstHashEntry(hash,&search),i=0 ;
     *	       hPtr!=NULL ; hPtr=Tcl_NextHashEntry(&search),i++) {
     *     ensemblePtr->subcommandArrayPtr[i] = Tcl_GetHashKey(hash, &hPtr);
     * }
     *
     * can produce long runs of precisely ordered table entries when the
     * commands in the namespace are declared in a sorted fashion (an ordering
     * some people like) and the hashing functions (or the command names
     * themselves) are fairly unfortunate. By filling from both ends, it
     * requires active malice (and probably a debugger) to get qsort() to have
     * awful runtime behaviour.
     */

    i = 0;
    j = hash->numEntries;
    hPtr = Tcl_FirstHashEntry(hash, &search);
    while (hPtr != NULL) {
	ensemblePtr->subcommandArrayPtr[i++] = Tcl_GetHashKey(hash, hPtr);
	hPtr = Tcl_NextHashEntry(&search);
	if (hPtr == NULL) {
	    break;
	}
	ensemblePtr->subcommandArrayPtr[--j] = Tcl_GetHashKey(hash, hPtr);
	hPtr = Tcl_NextHashEntry(&search);
    }
    if (hash->numEntries > 1) {
	qsort(ensemblePtr->subcommandArrayPtr, (unsigned) hash->numEntries,
		sizeof(char *), NsEnsembleStringOrder);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * NsEnsembleStringOrder --
 *
 *	Helper function to compare two pointers to two strings for use with
 *	qsort().
 *
 * Results:
 *	-1 if the first string is smaller, 1 if the second string is smaller,
 *	and 0 if they are equal.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static int
NsEnsembleStringOrder(
    const void *strPtr1,
    const void *strPtr2)
{
    return strcmp(*(const char **)strPtr1, *(const char **)strPtr2);
}

/*
 *----------------------------------------------------------------------
 *
 * FreeEnsembleCmdRep --
 *
 *	Destroys the internal representation of a Tcl_Obj that has been
 *	holding information about a command in an ensemble.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Memory is deallocated. If this held the last reference to a
 *	namespace's main structure, that main structure will also be
 *	destroyed.
 *
 *----------------------------------------------------------------------
 */

static void
FreeEnsembleCmdRep(
    Tcl_Obj *objPtr)
{
    EnsembleCmdRep *ensembleCmd = objPtr->internalRep.twoPtrValue.ptr1;

    ckfree(ensembleCmd);
    objPtr->typePtr = NULL;
}

/*
 *----------------------------------------------------------------------
 *
 * DupEnsembleCmdRep --
 *
 *	Makes one Tcl_Obj into a copy of another that is a subcommand of an
 *	ensemble.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Memory is allocated, and the namespace that the ensemble is built on
 *	top of gains another reference.
 *
 *----------------------------------------------------------------------
 */

static void
DupEnsembleCmdRep(
    Tcl_Obj *objPtr,
    Tcl_Obj *copyPtr)
{
    EnsembleCmdRep *ensembleCmd = objPtr->internalRep.twoPtrValue.ptr1;
    EnsembleCmdRep *ensembleCopy = ckalloc(sizeof(EnsembleCmdRep));

    copyPtr->typePtr = &tclEnsembleCmdType;
    copyPtr->internalRep.twoPtrValue.ptr1 = ensembleCopy;
    ensembleCopy->epoch = ensembleCmd->epoch;
    ensembleCopy->token = ensembleCmd->token;
    ensembleCopy->tablePtr = ensembleCmd->tablePtr;
    ensembleCopy->hPtr = ensembleCmd->hPtr;
}

/*
 *----------------------------------------------------------------------
 *
 * TclCompileEnsemble --
 *
 *	Procedure called to compile an ensemble command. Note that most
 *	ensembles are not compiled, since modifying a compiled ensemble causes
 *	a invalidation of all existing bytecode (expensive!) which is not
 *	normally warranted.
 *
 * Results:
 *	Returns TCL_OK for a successful compile. Returns TCL_ERROR to defer
 *	evaluation to runtime.
 *
 * Side effects:
 *	Instructions are added to envPtr to execute the subcommands of the
 *	ensemble at runtime if a compile-time mapping is possible.
 *
 *----------------------------------------------------------------------
 */

int
TclCompileEnsemble(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
				 * created by Tcl_ParseCommand. */
    Command *cmdPtr,		/* Points to defintion of command being
				 * compiled. */
    CompileEnv *envPtr)		/* Holds resulting instructions. */
{
    Tcl_Token *tokenPtr = TokenAfter(parsePtr->tokenPtr);
    Tcl_Obj *mapObj, *subcmdObj, *targetCmdObj, *listObj, **elems;
    Tcl_Obj *replaced = Tcl_NewObj(), *replacement;
    Tcl_Command ensemble = (Tcl_Command) cmdPtr;
    Command *oldCmdPtr = cmdPtr, *newCmdPtr;
    int len, result, flags = 0, i, depth = 1, invokeAnyway = 0;
    int ourResult = TCL_ERROR;
    unsigned numBytes;
    const char *word;
    DefineLineInformation;

    Tcl_IncrRefCount(replaced);
    if (parsePtr->numWords < depth + 1) {
	goto failed;
    }
    if (tokenPtr->type != TCL_TOKEN_SIMPLE_WORD) {
	/*
	 * Too hard.
	 */

	goto failed;
    }

    /*
     * This is where we return to if we are parsing multiple nested compiled
     * ensembles. [info object] is such a beast.
     */

  checkNextWord:
    word = tokenPtr[1].start;
    numBytes = tokenPtr[1].size;

    /*
     * There's a sporting chance we'll be able to compile this. But now we
     * must check properly. To do that, check that we're compiling an ensemble
     * that has a compilable command as its appropriate subcommand.
     */

    if (Tcl_GetEnsembleMappingDict(NULL, ensemble, &mapObj) != TCL_OK
	    || mapObj == NULL) {
	/*
	 * Either not an ensemble or a mapping isn't installed. Crud. Too hard
	 * to proceed.
	 */

	goto failed;
    }

    /*
     * Also refuse to compile anything that uses a formal parameter list for
     * now, on the grounds that it is too complex.
     */

    if (Tcl_GetEnsembleParameterList(NULL, ensemble, &listObj) != TCL_OK
	    || listObj != NULL) {
	/*
	 * Figuring out how to compile this has become too much. Bail out.
	 */

	goto failed;
    }

    /*
     * Next, get the flags. We need them on several code paths so that we can
     * know whether we're to do prefix matching.
     */

    (void) Tcl_GetEnsembleFlags(NULL, ensemble, &flags);

    /*
     * Check to see if there's also a subcommand list; must check to see if
     * the subcommand we are calling is in that list if it exists, since that
     * list filters the entries in the map.
     */

    (void) Tcl_GetEnsembleSubcommandList(NULL, ensemble, &listObj);
    if (listObj != NULL) {
	int sclen;
	const char *str;
	Tcl_Obj *matchObj = NULL;

	if (Tcl_ListObjGetElements(NULL, listObj, &len, &elems) != TCL_OK) {
	    goto failed;
	}
	for (i=0 ; i<len ; i++) {
	    str = Tcl_GetStringFromObj(elems[i], &sclen);
	    if ((sclen == (int) numBytes) && !memcmp(word, str, numBytes)) {
		/*
		 * Exact match! Excellent!
		 */

		result = Tcl_DictObjGet(NULL, mapObj,elems[i], &targetCmdObj);
		if (result != TCL_OK || targetCmdObj == NULL) {
		    goto failed;
		}
		replacement = elems[i];
		goto doneMapLookup;
	    }

	    /*
	     * Check to see if we've got a prefix match. A single prefix match
	     * is fine, and allows us to refine our dictionary lookup, but
	     * multiple prefix matches is a Bad Thing and will prevent us from
	     * making progress. Note that we cannot do the lookup immediately
	     * in the prefix case; might be another entry later in the list
	     * that causes things to fail.
	     */

	    if ((flags & TCL_ENSEMBLE_PREFIX)
		    && strncmp(word, str, numBytes) == 0) {
		if (matchObj != NULL) {
		    goto failed;
		}
		matchObj = elems[i];
	    }
	}
	if (matchObj == NULL) {
	    goto failed;
	}
	result = Tcl_DictObjGet(NULL, mapObj, matchObj, &targetCmdObj);
	if (result != TCL_OK || targetCmdObj == NULL) {
	    goto failed;
	}
	replacement = matchObj;
    } else {
	Tcl_DictSearch s;
	int done, matched;
	Tcl_Obj *tmpObj;

	/*
	 * No map, so check the dictionary directly.
	 */

	TclNewStringObj(subcmdObj, word, (int) numBytes);
	result = Tcl_DictObjGet(NULL, mapObj, subcmdObj, &targetCmdObj);
	if (result == TCL_OK && targetCmdObj != NULL) {
	    /*
	     * Got it. Skip the fiddling around with prefixes.
	     */

	    replacement = subcmdObj;
	    goto doneMapLookup;
	}
	TclDecrRefCount(subcmdObj);

	/*
	 * We've not literally got a valid subcommand. But maybe we have a
	 * prefix. Check if prefix matches are allowed.
	 */

	if (!(flags & TCL_ENSEMBLE_PREFIX)) {
	    goto failed;
	}

	/*
	 * Iterate over the keys in the dictionary, checking to see if we're a
	 * prefix.
	 */

	Tcl_DictObjFirst(NULL, mapObj, &s, &subcmdObj, &tmpObj, &done);
	matched = 0;
	replacement = NULL;		/* Silence, fool compiler! */
	while (!done) {
	    if (strncmp(TclGetString(subcmdObj), word, numBytes) == 0) {
		if (matched++) {
		    /*
		     * Must have matched twice! Not unique, so no point
		     * looking further.
		     */

		    break;
		}
		replacement = subcmdObj;
		targetCmdObj = tmpObj;
	    }
	    Tcl_DictObjNext(&s, &subcmdObj, &tmpObj, &done);
	}
	Tcl_DictObjDone(&s);

	/*
	 * If we have anything other than a single match, we've failed the
	 * unique prefix check.
	 */

	if (matched != 1) {
	    invokeAnyway = 1;
	    goto failed;
	}
    }

    /*
     * OK, we definitely map to something. But what?
     *
     * The command we map to is the first word out of the map element. Note
     * that we also reject dealing with multi-element rewrites if we are in a
     * safe interpreter, as there is otherwise a (highly gnarly!) way to make
     * Tcl crash open to exploit.
     */

  doneMapLookup:
    Tcl_ListObjAppendElement(NULL, replaced, replacement);
    if (Tcl_ListObjGetElements(NULL, targetCmdObj, &len, &elems) != TCL_OK) {
	goto failed;
    } else if (len != 1) {
	/*
	 * Note that at this point we know we can't issue any special
	 * instruction sequence as the mapping isn't one that we support at
	 * the compiled level.
	 */

	goto cleanup;
    }
    targetCmdObj = elems[0];

    oldCmdPtr = cmdPtr;
    Tcl_IncrRefCount(targetCmdObj);
    newCmdPtr = (Command *) Tcl_GetCommandFromObj(interp, targetCmdObj);
    TclDecrRefCount(targetCmdObj);
    if (newCmdPtr == NULL || Tcl_IsSafe(interp)
	    || newCmdPtr->nsPtr->flags & NS_SUPPRESS_COMPILATION
	    || newCmdPtr->flags & CMD_HAS_EXEC_TRACES
	    || ((Interp *)interp)->flags & DONT_COMPILE_CMDS_INLINE) {
	/*
	 * Maps to an undefined command or a command without a compiler.
	 * Cannot compile.
	 */

	goto cleanup;
    }
    cmdPtr = newCmdPtr;
    depth++;

    /*
     * See whether we have a nested ensemble. If we do, we can go round the
     * mulberry bush again, consuming the next word.
     */

    if (cmdPtr->compileProc == TclCompileEnsemble) {
	tokenPtr = TokenAfter(tokenPtr);
	if (parsePtr->numWords < depth + 1
		|| tokenPtr->type != TCL_TOKEN_SIMPLE_WORD) {
	    /*
	     * Too hard because the user has done something unpleasant like
	     * omitting the sub-ensemble's command name or used a non-constant
	     * name for a sub-ensemble's command name; we respond by bailing
	     * out completely (this is a rare case). [Bug 6d2f249a01]
	     */

	    goto cleanup;
	}
	ensemble = (Tcl_Command) cmdPtr;
	goto checkNextWord;
    }

    /*
     * Now we've done the mapping process, can now actually try to compile.
     * If there is a subcommand compiler and that successfully produces code,
     * we'll use that. Otherwise, we fall back to generating opcodes to do the
     * invoke at runtime.
     */

    invokeAnyway = 1;
    if (TCL_OK == TclAttemptCompileProc(interp, parsePtr, depth, cmdPtr,
	    envPtr)) {
	ourResult = TCL_OK;
	goto cleanup;
    }

    /*
     * Throw out any line information generated by the failed compile attempt.
     */

    while (mapPtr->nuloc - 1 > eclIndex) {
        mapPtr->nuloc--;
        ckfree(mapPtr->loc[mapPtr->nuloc].line);
        mapPtr->loc[mapPtr->nuloc].line = NULL;
    }

    /*
     * Reset the index of next command.  Toss out any from failed nested
     * partial compiles.
     */

    envPtr->numCommands = mapPtr->nuloc;

    /*
     * Failed to do a full compile for some reason. Try to do a direct invoke
     * instead of going through the ensemble lookup process again.
     */

  failed:
    if (depth < 250) {
	if (depth > 1) {
	    if (!invokeAnyway) {
		cmdPtr = oldCmdPtr;
		depth--;
	    }
	}
	/*
	 * The length of the "replaced" list must be depth-1.  Trim back
	 * any extra elements that might have been appended by failing
	 * pathways above.
	 */
	(void) Tcl_ListObjReplace(NULL, replaced, depth-1, INT_MAX, 0, NULL);

	/*
	 * TODO: Reconsider whether we ought to call CompileToInvokedCommand()
	 * when depth==1.  In that case we are choosing to emit the
	 * INST_INVOKE_REPLACE bytecode when there is in fact no replacing
	 * to be done.  It would be equally functional and presumably more
	 * performant to fall through to cleanup below, return TCL_ERROR,
	 * and let the compiler harness emit the INST_INVOKE_STK
	 * implementation for us.
	 */

	CompileToInvokedCommand(interp, parsePtr, replaced, cmdPtr, envPtr);
	ourResult = TCL_OK;
    }

    /*
     * Release the memory we allocated. If we've got here, we've either done
     * something useful or we're in a case that we can't compile at all and
     * we're just giving up.
     */

  cleanup:
    Tcl_DecrRefCount(replaced);
    return ourResult;
}

int
TclAttemptCompileProc(
    Tcl_Interp *interp,
    Tcl_Parse *parsePtr,
    int depth,
    Command *cmdPtr,
    CompileEnv *envPtr)		/* Holds resulting instructions. */
{
    int result, i;
    Tcl_Token *saveTokenPtr = parsePtr->tokenPtr;
    int savedStackDepth = envPtr->currStackDepth;
    unsigned savedCodeNext = envPtr->codeNext - envPtr->codeStart;
    int savedAuxDataArrayNext = envPtr->auxDataArrayNext;
    int savedExceptArrayNext = envPtr->exceptArrayNext;
#ifdef TCL_COMPILE_DEBUG
    int savedExceptDepth = envPtr->exceptDepth;
#endif
    DefineLineInformation;

    if (cmdPtr->compileProc == NULL) {
	return TCL_ERROR;
    }

    /*
     * Advance parsePtr->tokenPtr so that it points at the last subcommand.
     * This will be wrong, but it will not matter, and it will put the
     * tokens for the arguments in the right place without the needed to
     * allocate a synthetic Tcl_Parse struct, or copy tokens around.
     */

    for (i = 0; i < depth - 1; i++) {
	parsePtr->tokenPtr = TokenAfter(parsePtr->tokenPtr);
    }
    parsePtr->numWords -= (depth - 1);

    /*
     * Shift the line information arrays to account for different word
     * index values.
     */

    mapPtr->loc[eclIndex].line += (depth - 1);
    mapPtr->loc[eclIndex].next += (depth - 1);

    /*
     * Hand off compilation to the subcommand compiler. At last!
     */

    result = cmdPtr->compileProc(interp, parsePtr, cmdPtr, envPtr);

    /*
     * Undo the shift.
     */

    mapPtr->loc[eclIndex].line -= (depth - 1);
    mapPtr->loc[eclIndex].next -= (depth - 1);

    parsePtr->numWords += (depth - 1);
    parsePtr->tokenPtr = saveTokenPtr;

    /*
     * If our target failed to compile, revert any data from failed partial
     * compiles.  Note that envPtr->numCommands need not be checked because
     * we avoid compiling subcommands that recursively call TclCompileScript().
     */

#ifdef TCL_COMPILE_DEBUG
    if (envPtr->exceptDepth != savedExceptDepth) {
	Tcl_Panic("ExceptionRange Starts and Ends do not balance");
    }
#endif

    if (result != TCL_OK) {
	ExceptionAux *auxPtr = envPtr->exceptAuxArrayPtr;

	for (i = 0; i < savedExceptArrayNext; i++) {
	    while (auxPtr->numBreakTargets > 0
		    && auxPtr->breakTargets[auxPtr->numBreakTargets - 1]
		    >= savedCodeNext) {
		auxPtr->numBreakTargets--;
	    }
	    while (auxPtr->numContinueTargets > 0
		    && auxPtr->continueTargets[auxPtr->numContinueTargets - 1]
		    >= savedCodeNext) {
		auxPtr->numContinueTargets--;
	    }
	    auxPtr++;
	}
	envPtr->exceptArrayNext = savedExceptArrayNext;

	if (savedAuxDataArrayNext != envPtr->auxDataArrayNext) {
	    AuxData *auxDataPtr = envPtr->auxDataArrayPtr;
	    AuxData *auxDataEnd = auxDataPtr;

	    auxDataPtr += savedAuxDataArrayNext;
	    auxDataEnd += envPtr->auxDataArrayNext;

	    while (auxDataPtr < auxDataEnd) {
		if (auxDataPtr->type->freeProc != NULL) {
		    auxDataPtr->type->freeProc(auxDataPtr->clientData);
		}
		auxDataPtr++;
	    }
	    envPtr->auxDataArrayNext = savedAuxDataArrayNext;
	}
	envPtr->currStackDepth = savedStackDepth;
	envPtr->codeNext = envPtr->codeStart + savedCodeNext;
#ifdef TCL_COMPILE_DEBUG
    } else {
	/*
	 * Confirm that the command compiler generated a single value on
	 * the stack as its result. This is only done in debugging mode,
	 * as it *should* be correct and normal users have no reasonable
	 * way to fix it anyway.
	 */

	int diff = envPtr->currStackDepth - savedStackDepth;

	if (diff != 1) {
	    Tcl_Panic("bad stack adjustment when compiling"
		    " %.*s (was %d instead of 1)", parsePtr->tokenPtr->size,
		    parsePtr->tokenPtr->start, diff);
	}
#endif
    }

    return result;
}

/*
 * How to compile a subcommand to a _replacing_ invoke of its implementation
 * command.
 */

static void
CompileToInvokedCommand(
    Tcl_Interp *interp,
    Tcl_Parse *parsePtr,
    Tcl_Obj *replacements,
    Command *cmdPtr,
    CompileEnv *envPtr)		/* Holds resulting instructions. */
{
    Tcl_Token *tokPtr;
    Tcl_Obj *objPtr, **words;
    char *bytes;
    int length, i, numWords, cmdLit;
    DefineLineInformation;

    /*
     * Push the words of the command. Take care; the command words may be
     * scripts that have backslashes in them, and [info frame 0] can see the
     * difference. Hence the call to TclContinuationsEnterDerived...
     */

    Tcl_ListObjGetElements(NULL, replacements, &numWords, &words);
    for (i = 0, tokPtr = parsePtr->tokenPtr; i < parsePtr->numWords;
	    i++, tokPtr = TokenAfter(tokPtr)) {
	if (i > 0 && i < numWords+1) {
	    bytes = Tcl_GetStringFromObj(words[i-1], &length);
	    PushLiteral(envPtr, bytes, length);
	    continue;
	}

	SetLineInformation(i);
	if (tokPtr->type == TCL_TOKEN_SIMPLE_WORD) {
	    int literal = TclRegisterNewLiteral(envPtr,
		    tokPtr[1].start, tokPtr[1].size);

	    if (envPtr->clNext) {
		TclContinuationsEnterDerived(
			TclFetchLiteral(envPtr, literal),
			tokPtr[1].start - envPtr->source,
			envPtr->clNext);
	    }
	    TclEmitPush(literal, envPtr);
	} else {
	    CompileTokens(envPtr, tokPtr, interp);
	}
    }

    /*
     * Push the name of the command we're actually dispatching to as part of
     * the implementation.
     */

    objPtr = Tcl_NewObj();
    Tcl_GetCommandFullName(interp, (Tcl_Command) cmdPtr, objPtr);
    bytes = Tcl_GetStringFromObj(objPtr, &length);
    cmdLit = TclRegisterNewCmdLiteral(envPtr, bytes, length);
    TclSetCmdNameObj(interp, TclFetchLiteral(envPtr, cmdLit), cmdPtr);
    TclEmitPush(cmdLit, envPtr);
    TclDecrRefCount(objPtr);

    /*
     * Do the replacing dispatch.
     */

    TclEmitInvoke(envPtr, INST_INVOKE_REPLACE, parsePtr->numWords,numWords+1);
}

/*
 * Helpers that do issuing of instructions for commands that "don't have
 * compilers" (well, they do; these). They all work by just generating base
 * code to invoke the command; they're intended for ensemble subcommands so
 * that the costs of INST_INVOKE_REPLACE can be avoided where we can work out
 * that they're not needed.
 *
 * Note that these are NOT suitable for commands where there's an argument
 * that is a script, as an [info level] or [info frame] in the inner context
 * can see the difference.
 */

static int
CompileBasicNArgCommand(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
				 * created by Tcl_ParseCommand. */
    Command *cmdPtr,		/* Points to defintion of command being
				 * compiled. */
    CompileEnv *envPtr)		/* Holds resulting instructions. */
{
    Tcl_Obj *objPtr = Tcl_NewObj();

    Tcl_IncrRefCount(objPtr);
    Tcl_GetCommandFullName(interp, (Tcl_Command) cmdPtr, objPtr);
    TclCompileInvocation(interp, parsePtr->tokenPtr, objPtr,
	    parsePtr->numWords, envPtr);
    Tcl_DecrRefCount(objPtr);
    return TCL_OK;
}

int
TclCompileBasic0ArgCmd(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
				 * created by Tcl_ParseCommand. */
    Command *cmdPtr,		/* Points to defintion of command being
				 * compiled. */
    CompileEnv *envPtr)		/* Holds resulting instructions. */
{
    /*
     * Verify that the number of arguments is correct; that's the only case
     * that we know will avoid the call to Tcl_WrongNumArgs() at invoke time,
     * which is the only code that sees the shenanigans of ensemble dispatch.
     */

    if (parsePtr->numWords != 1) {
	return TCL_ERROR;
    }

    return CompileBasicNArgCommand(interp, parsePtr, cmdPtr, envPtr);
}

int
TclCompileBasic1ArgCmd(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
				 * created by Tcl_ParseCommand. */
    Command *cmdPtr,		/* Points to defintion of command being
				 * compiled. */
    CompileEnv *envPtr)		/* Holds resulting instructions. */
{
    /*
     * Verify that the number of arguments is correct; that's the only case
     * that we know will avoid the call to Tcl_WrongNumArgs() at invoke time,
     * which is the only code that sees the shenanigans of ensemble dispatch.
     */

    if (parsePtr->numWords != 2) {
	return TCL_ERROR;
    }

    return CompileBasicNArgCommand(interp, parsePtr, cmdPtr, envPtr);
}

int
TclCompileBasic2ArgCmd(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
				 * created by Tcl_ParseCommand. */
    Command *cmdPtr,		/* Points to defintion of command being
				 * compiled. */
    CompileEnv *envPtr)		/* Holds resulting instructions. */
{
    /*
     * Verify that the number of arguments is correct; that's the only case
     * that we know will avoid the call to Tcl_WrongNumArgs() at invoke time,
     * which is the only code that sees the shenanigans of ensemble dispatch.
     */

    if (parsePtr->numWords != 3) {
	return TCL_ERROR;
    }

    return CompileBasicNArgCommand(interp, parsePtr, cmdPtr, envPtr);
}

int
TclCompileBasic3ArgCmd(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
				 * created by Tcl_ParseCommand. */
    Command *cmdPtr,		/* Points to defintion of command being
				 * compiled. */
    CompileEnv *envPtr)		/* Holds resulting instructions. */
{
    /*
     * Verify that the number of arguments is correct; that's the only case
     * that we know will avoid the call to Tcl_WrongNumArgs() at invoke time,
     * which is the only code that sees the shenanigans of ensemble dispatch.
     */

    if (parsePtr->numWords != 4) {
	return TCL_ERROR;
    }

    return CompileBasicNArgCommand(interp, parsePtr, cmdPtr, envPtr);
}

int
TclCompileBasic0Or1ArgCmd(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
				 * created by Tcl_ParseCommand. */
    Command *cmdPtr,		/* Points to defintion of command being
				 * compiled. */
    CompileEnv *envPtr)		/* Holds resulting instructions. */
{
    /*
     * Verify that the number of arguments is correct; that's the only case
     * that we know will avoid the call to Tcl_WrongNumArgs() at invoke time,
     * which is the only code that sees the shenanigans of ensemble dispatch.
     */

    if (parsePtr->numWords != 1 && parsePtr->numWords != 2) {
	return TCL_ERROR;
    }

    return CompileBasicNArgCommand(interp, parsePtr, cmdPtr, envPtr);
}

int
TclCompileBasic1Or2ArgCmd(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
				 * created by Tcl_ParseCommand. */
    Command *cmdPtr,		/* Points to defintion of command being
				 * compiled. */
    CompileEnv *envPtr)		/* Holds resulting instructions. */
{
    /*
     * Verify that the number of arguments is correct; that's the only case
     * that we know will avoid the call to Tcl_WrongNumArgs() at invoke time,
     * which is the only code that sees the shenanigans of ensemble dispatch.
     */

    if (parsePtr->numWords != 2 && parsePtr->numWords != 3) {
	return TCL_ERROR;
    }

    return CompileBasicNArgCommand(interp, parsePtr, cmdPtr, envPtr);
}

int
TclCompileBasic2Or3ArgCmd(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
				 * created by Tcl_ParseCommand. */
    Command *cmdPtr,		/* Points to defintion of command being
				 * compiled. */
    CompileEnv *envPtr)		/* Holds resulting instructions. */
{
    /*
     * Verify that the number of arguments is correct; that's the only case
     * that we know will avoid the call to Tcl_WrongNumArgs() at invoke time,
     * which is the only code that sees the shenanigans of ensemble dispatch.
     */

    if (parsePtr->numWords != 3 && parsePtr->numWords != 4) {
	return TCL_ERROR;
    }

    return CompileBasicNArgCommand(interp, parsePtr, cmdPtr, envPtr);
}

int
TclCompileBasic0To2ArgCmd(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
				 * created by Tcl_ParseCommand. */
    Command *cmdPtr,		/* Points to defintion of command being
				 * compiled. */
    CompileEnv *envPtr)		/* Holds resulting instructions. */
{
    /*
     * Verify that the number of arguments is correct; that's the only case
     * that we know will avoid the call to Tcl_WrongNumArgs() at invoke time,
     * which is the only code that sees the shenanigans of ensemble dispatch.
     */

    if (parsePtr->numWords < 1 || parsePtr->numWords > 3) {
	return TCL_ERROR;
    }

    return CompileBasicNArgCommand(interp, parsePtr, cmdPtr, envPtr);
}

int
TclCompileBasic1To3ArgCmd(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
				 * created by Tcl_ParseCommand. */
    Command *cmdPtr,		/* Points to defintion of command being
				 * compiled. */
    CompileEnv *envPtr)		/* Holds resulting instructions. */
{
    /*
     * Verify that the number of arguments is correct; that's the only case
     * that we know will avoid the call to Tcl_WrongNumArgs() at invoke time,
     * which is the only code that sees the shenanigans of ensemble dispatch.
     */

    if (parsePtr->numWords < 2 || parsePtr->numWords > 4) {
	return TCL_ERROR;
    }

    return CompileBasicNArgCommand(interp, parsePtr, cmdPtr, envPtr);
}

int
TclCompileBasicMin0ArgCmd(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
				 * created by Tcl_ParseCommand. */
    Command *cmdPtr,		/* Points to defintion of command being
				 * compiled. */
    CompileEnv *envPtr)		/* Holds resulting instructions. */
{
    /*
     * Verify that the number of arguments is correct; that's the only case
     * that we know will avoid the call to Tcl_WrongNumArgs() at invoke time,
     * which is the only code that sees the shenanigans of ensemble dispatch.
     */

    if (parsePtr->numWords < 1) {
	return TCL_ERROR;
    }

    return CompileBasicNArgCommand(interp, parsePtr, cmdPtr, envPtr);
}

int
TclCompileBasicMin1ArgCmd(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
				 * created by Tcl_ParseCommand. */
    Command *cmdPtr,		/* Points to defintion of command being
				 * compiled. */
    CompileEnv *envPtr)		/* Holds resulting instructions. */
{
    /*
     * Verify that the number of arguments is correct; that's the only case
     * that we know will avoid the call to Tcl_WrongNumArgs() at invoke time,
     * which is the only code that sees the shenanigans of ensemble dispatch.
     */

    if (parsePtr->numWords < 2) {
	return TCL_ERROR;
    }

    return CompileBasicNArgCommand(interp, parsePtr, cmdPtr, envPtr);
}

int
TclCompileBasicMin2ArgCmd(
    Tcl_Interp *interp,		/* Used for error reporting. */
    Tcl_Parse *parsePtr,	/* Points to a parse structure for the command
				 * created by Tcl_ParseCommand. */
    Command *cmdPtr,		/* Points to defintion of command being
				 * compiled. */
    CompileEnv *envPtr)		/* Holds resulting instructions. */
{
    /*
     * Verify that the number of arguments is correct; that's the only case
     * that we know will avoid the call to Tcl_WrongNumArgs() at invoke time,
     * which is the only code that sees the shenanigans of ensemble dispatch.
     */

    if (parsePtr->numWords < 3) {
	return TCL_ERROR;
    }

    return CompileBasicNArgCommand(interp, parsePtr, cmdPtr, envPtr);
}

/*
 * Local Variables:
 * mode: c
 * c-basic-offset: 4
 * fill-column: 78
 * End:
 */