diff options
Diffstat (limited to 'generic/tclCompCmdsGR.c')
| -rw-r--r-- | generic/tclCompCmdsGR.c | 128 |
1 files changed, 19 insertions, 109 deletions
diff --git a/generic/tclCompCmdsGR.c b/generic/tclCompCmdsGR.c index e2ddb11..396947c 100644 --- a/generic/tclCompCmdsGR.c +++ b/generic/tclCompCmdsGR.c @@ -35,45 +35,7 @@ static int IndexTailVarIfKnown(Tcl_Interp *interp, * TclGetIndexFromToken -- * * Parse a token to determine if an index value is known at - * compile time. Two cases are possible. The compile time value - * of the token might be parsed as an absolute index value - * in the C signed int range. Note that this includes index - * values that are integers as presented as well as index - * arithmetic expressions that can be fully computed at compile - * time. The absolute index values that can be directly meaningful - * as an index into either a list or a string are those integer - * values >= TCL_INDEX_START (0) and < TCL_INDEX_AFTER (INT_MAX). - * The largest string supported in Tcl 8 has bytelength INT_MAX. - * This means the largest character supported length is also INT_MAX, - * and the index of the last character in a string of length INT_MAX - * is INT_MAX-1. - * - * Any absolute index value parsed outside that range is encoded - * using the minBoundary and maxBounday values passed in by the - * caller as the encoding to use for indices that are either - * less than or greater than the usable index range. TCL_INDEX_AFTER - * is available as a good choice for most callers to use for - * maxBoundary. Likewise, the value TCL_INDEX_BEFORE is good for - * most callers to use for minBoundary. Other values are possible - * when the caller knows it is helpful in producing its own behavior - * for indices before and after the indexed item. - * - * A token can also be parsed as an end-relative index expression. - * All end-relative expressions that indicate an index larger - * than end (end+2, end--5) point beyond the end of the indexed - * collection, and can be encoded as maxBoundary. The end-relative - * expressions that indicate an index less than or equal to end - * are encoded relative to the value TCL_INDEX_END (-2). The - * index "end" is encoded as -2, down to the index "end-0x7ffffffe" - * which is encoded as INT_MIN. Since the largest index into a - * string possible in Tcl 8 is 0x7ffffffe, the interpretation of - * "end-0x7ffffffe" for that largest string would be 0. Thus, - * if the tokens "end-0x7fffffff" or "end+-0x80000000" are parsed, - * they can be encoded with the minBoundary value. - * - * These details will require re-examination whenever string and - * list length limits are increased, but that will likely also - * mean a revised routine capable of returning Tcl_WideInt values. + * compile time. * * Returns: * TCL_OK if parsing succeeded, and TCL_ERROR if it failed. @@ -88,69 +50,17 @@ static int IndexTailVarIfKnown(Tcl_Interp *interp, int TclGetIndexFromToken( Tcl_Token *tokenPtr, - int *index, - int minBoundary, - int maxBoundary) + int before, + int after, + int *indexPtr) { Tcl_Obj *tmpObj = Tcl_NewObj(); - int result, idx; + int result = TCL_ERROR; - if (!TclWordKnownAtCompileTime(tokenPtr, tmpObj)) { - Tcl_DecrRefCount(tmpObj); - return TCL_ERROR; - } - - result = TclGetIntFromObj(NULL, tmpObj, &idx); - if (result == TCL_OK) { - /* We parsed a value in the range INT_MIN...INT_MAX */ - integerEncode: - if (idx < TCL_INDEX_START) { - /* All negative absolute indices are "before the beginning" */ - idx = minBoundary; - } else if (idx == INT_MAX) { - /* This index value is always "after the end" */ - idx = maxBoundary; - } - /* usual case, the absolute index value encodes itself */ - } else { - result = TclGetEndOffsetFromObj(NULL, tmpObj, 0, &idx); - if (result == TCL_OK) { - /* - * We parsed an end+offset index value. - * idx holds the offset value in the range INT_MIN...INT_MAX. - */ - if (idx > 0) { - /* - * All end+postive or end-negative expressions - * always indicate "after the end". - */ - idx = maxBoundary; - } else if (idx < INT_MIN - TCL_INDEX_END) { - /* These indices always indicate "before the beginning */ - idx = minBoundary; - } else { - /* Encoded end-positive (or end+negative) are offset */ - idx += TCL_INDEX_END; - } - } else { - result = TclGetIntForIndexM(NULL, tmpObj, 0, &idx); - if (result == TCL_OK) { - /* - * Only reach this case when the index value is a - * constant index arithmetic expression, and idx - * holds the result. Treat it the same as if it were - * parsed as an absolute integer value. - */ - goto integerEncode; - } - } + if (TclWordKnownAtCompileTime(tokenPtr, tmpObj)) { + result = TclIndexEncode(NULL, tmpObj, before, after, indexPtr); } Tcl_DecrRefCount(tmpObj); - - if (result == TCL_OK) { - *index = idx; - } - return result; } @@ -1177,8 +1087,8 @@ TclCompileLindexCmd( } idxTokenPtr = TokenAfter(valTokenPtr); - if (TclGetIndexFromToken(idxTokenPtr, &idx, TCL_INDEX_BEFORE, - TCL_INDEX_BEFORE) == TCL_OK) { + if (TclGetIndexFromToken(idxTokenPtr, TCL_INDEX_BEFORE, TCL_INDEX_BEFORE, + &idx) == TCL_OK) { /* * The idxTokenPtr parsed as a valid index value and was * encoded as expected by INST_LIST_INDEX_IMM. @@ -1406,8 +1316,8 @@ TclCompileLrangeCmd( listTokenPtr = TokenAfter(parsePtr->tokenPtr); tokenPtr = TokenAfter(listTokenPtr); - if (TclGetIndexFromToken(tokenPtr, &idx1, TCL_INDEX_START, - TCL_INDEX_AFTER) != TCL_OK) { + if (TclGetIndexFromToken(tokenPtr, TCL_INDEX_START, TCL_INDEX_AFTER, + &idx1) != TCL_OK) { return TCL_ERROR; } /* @@ -1416,8 +1326,8 @@ TclCompileLrangeCmd( */ tokenPtr = TokenAfter(tokenPtr); - if (TclGetIndexFromToken(tokenPtr, &idx2, TCL_INDEX_BEFORE, - TCL_INDEX_END) != TCL_OK) { + if (TclGetIndexFromToken(tokenPtr, TCL_INDEX_BEFORE, TCL_INDEX_END, + &idx2) != TCL_OK) { return TCL_ERROR; } /* @@ -1481,8 +1391,8 @@ TclCompileLinsertCmd( * make that transformation here so we can use the optimized bytecode * as much as possible. */ - if (TclGetIndexFromToken(tokenPtr, &idx, TCL_INDEX_START, - TCL_INDEX_END) != TCL_OK) { + if (TclGetIndexFromToken(tokenPtr, TCL_INDEX_START, TCL_INDEX_END, + &idx) != TCL_OK) { return TCL_ERROR; } @@ -1571,14 +1481,14 @@ TclCompileLreplaceCmd( listTokenPtr = TokenAfter(parsePtr->tokenPtr); tokenPtr = TokenAfter(listTokenPtr); - if (TclGetIndexFromToken(tokenPtr, &idx1, TCL_INDEX_START, - TCL_INDEX_AFTER) != TCL_OK) { + if (TclGetIndexFromToken(tokenPtr, TCL_INDEX_START, TCL_INDEX_AFTER, + &idx1) != TCL_OK) { return TCL_ERROR; } tokenPtr = TokenAfter(tokenPtr); - if (TclGetIndexFromToken(tokenPtr, &idx2, TCL_INDEX_BEFORE, - TCL_INDEX_END) != TCL_OK) { + if (TclGetIndexFromToken(tokenPtr, TCL_INDEX_BEFORE, TCL_INDEX_END, + &idx2) != TCL_OK) { return TCL_ERROR; } |