Refactor TclScanElement() part of list parsing to take advantage of tables

constructed for the task of script parsing.  Ought to speed generation of
string representation of lists, though the effect is likely only noticeable
on long lists made up primarily of simple elements (not needing quoting).

3 files changed, 37 insertions, 27 deletions

diff --git a/generic/tclParse.c b/generic/tclParse.c
index 3c984bf..f0050c6 100644
--- a/generic/tclParse.c
+++ b/generic/tclParse.c
@@ -14,6 +14,7 @@
  */
  
 #include "tclInt.h"
+#include "tclParse.h"
 
 /*
  * The following table provides parsing information about each possible 8-bit
@@ -41,18 +42,7 @@
  * TYPE_BRACE -		Character is a curly brace (either left or right).
  */
 
-#define TYPE_NORMAL		0
-#define TYPE_SPACE		0x1
-#define TYPE_COMMAND_END	0x2
-#define TYPE_SUBS		0x4
-#define TYPE_QUOTE		0x8
-#define TYPE_CLOSE_PAREN	0x10
-#define TYPE_CLOSE_BRACK	0x20
-#define TYPE_BRACE		0x40
-
-#define CHAR_TYPE(c) (charTypeTable+128)[(int)(c)]
-
-static const char charTypeTable[] = {
+const char charTypeTable[] = {
     /*
      * Negative character values, from -128 to -1:
      */
diff --git a/generic/tclParse.h b/generic/tclParse.h
new file mode 100644
index 0000000..be1ab15
--- /dev/null
+++ b/generic/tclParse.h
@@ -0,0 +1,17 @@
+/*
+ * Minimal set of shared macro definitions and declarations so that multiple
+ * source files can make use of the parsing table in tclParse.c
+ */
+
+#define TYPE_NORMAL		0
+#define TYPE_SPACE		0x1
+#define TYPE_COMMAND_END	0x2
+#define TYPE_SUBS		0x4
+#define TYPE_QUOTE		0x8
+#define TYPE_CLOSE_PAREN	0x10
+#define TYPE_CLOSE_BRACK	0x20
+#define TYPE_BRACE		0x40
+
+#define CHAR_TYPE(c) (charTypeTable+128)[(int)(c)]
+
+MODULE_SCOPE const char charTypeTable[];
diff --git a/generic/tclUtil.c b/generic/tclUtil.c
index 31c9fd3..6ce430b 100644
--- a/generic/tclUtil.c
+++ b/generic/tclUtil.c
@@ -13,6 +13,7 @@
  */
 
 #include "tclInt.h"
+#include "tclParse.h"
 #include <math.h>
 
 /*
@@ -972,15 +973,16 @@ TclScanElement(
     }
 
     while (length) {
+      if (CHAR_TYPE(*p) != TYPE_NORMAL) {
 	switch (*p) {
-	case '{':
+	case '{':	/* TYPE_BRACE */
 #if COMPAT
 	    braceCount++;
 #endif
 	    extra++;				/* Escape '{' => '\{' */
 	    nestingLevel++;
 	    break;
-	case '}':
+	case '}':	/* TYPE_BRACE */
 #if COMPAT
 	    braceCount++;
 #endif
@@ -991,8 +993,8 @@ TclScanElement(
 		requireEscape = 1;
 	    }
 	    break;
-	case ']':
-	case '"':
+	case ']':	/* TYPE_CLOSE_BRACK */
+	case '"':	/* TYPE_SPACE */
 #if COMPAT
 	    forbidNone = 1;
 	    extra++;		/* Escapes all just prepend a backslash */
@@ -1001,22 +1003,22 @@ TclScanElement(
 #else
 	    /* FLOW THROUGH */
 #endif
-	case '[':
-	case '$':
-	case ';':
-	case ' ':
-	case '\f':
-	case '\n':
-	case '\r':
-	case '\t':
-	case '\v':
+	case '[':	/* TYPE_SUBS */
+	case '$':	/* TYPE_SUBS */
+	case ';':	/* TYPE_COMMAND_END */
+	case ' ':	/* TYPE_SPACE */
+	case '\f':	/* TYPE_SPACE */
+	case '\n':	/* TYPE_COMMAND_END */
+	case '\r':	/* TYPE_SPACE */
+	case '\t':	/* TYPE_SPACE */
+	case '\v':	/* TYPE_SPACE */
 	    forbidNone = 1;
 	    extra++;		/* Escape sequences all one byte longer. */
 #if COMPAT
 	    preferBrace = 1;
 #endif
 	    break;
-	case '\\':
+	case '\\':	/* TYPE_SUBS */
 	    extra++;				/* Escape '\' => '\\' */
 	    if ((length == 1) || ((length == -1) && (p[1] == '\0'))) {
 		/* Final backslash. Cannot format with brace quoting. */
@@ -1041,13 +1043,14 @@ TclScanElement(
 	    preferBrace = 1;
 #endif
 	    break;
-	case '\0':
+	case '\0':	/* TYPE_SUBS */
 	    if (length == -1) {
 		goto endOfString;
 	    }
 	    /* TODO: Panic on improper encoding? */
 	    break;
 	}
+      }
 	length -= (length > 0);
 	p++;
     }