* Copyright (c) 1997 Sun Microsystems, Inc.
 * Copyright (c) 1998-2000 by Scriptics Corporation.
 * Contributions from Don Porter, NIST, 2006.  (not subject to US copyright)
 *
 * See the file "license.terms" for information on usage and redistribution of
 * this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tclCompExpr.c,v 1.67 2007/07/12 18:48:10 dgp Exp $
 */

#include "tclInt.h"
#include "tclCompile.h"		/* CompileEnv */

/*
 * Expression parsing takes place in the routine ParseExpr().  It takes a

    PREC_UNARY,		/* UNARY_PLUS */
    PREC_UNARY,		/* UNARY_MINUS */
    PREC_UNARY,		/* FUNCTION */
    PREC_START,		/* START */
    PREC_OPEN_PAREN,	/* OPEN_PAREN */
    PREC_UNARY,		/* NOT*/
    PREC_UNARY,		/* BIT_NOT*/

};

/*
 * The JumpList struct is used to create a stack of data needed for the
 * TclEmitForwardJump() and TclFixupForwardJump() calls that are performed
 * when compiling the short-circuiting operators QUESTION/COLON, AND, and OR.
 * Keeping a stack permits the CompileExprTree() routine to be non-recursive.

	 * litList, or a sequence of Tcl_Tokens representing a Tcl word
	 * getting appended to the parsePtr->tokens.  No OpNode is filled
	 * for this lexeme.
	 */

	case LEAF: {
	    Tcl_Token *tokenPtr;
	    const char *end = start;
	    int wordIndex;

	    /*
	     * A leaf operand appearing just after something that's not an
	     * operator is a syntax error.

	     */










	    if (NotOperator(lastParsed)) {
		msg = Tcl_ObjPrintf("missing operator at %s", mark);
		if (lastStart[0] == '0') {
		    Tcl_Obj *copy = Tcl_NewStringObj(lastStart,
			    start + scanned - lastStart);
		    if (TclCheckBadOctal(NULL, Tcl_GetString(copy))) {
			TclNewLiteralStringObj(post,
				"looks like invalid octal number");
		    }
		    Tcl_DecrRefCount(copy);
		}
		scanned = 0;
		insertMark = 1;
		parsePtr->errorType = TCL_PARSE_BAD_NUMBER;
		code = TCL_ERROR;

		/*
		 * Delay our escape from the parse loop until any literal
		 * can be appended to litList, making it available to our
		 * caller to be freed, to avoid leaking it.
		 */
	    }

	    switch (lexeme) {
	    case NUMBER:
	    case BOOLEAN:
		Tcl_ListObjAppendElement(NULL, litList, literal);
		lastParsed = OT_LITERAL;
		start += scanned;
		numBytes -= scanned;
		continue;
	    default:
		break;
	    }

	    if (code != TCL_OK) {
		/* Escaping the loop due to syntax error is fine now. */
		continue;
	    }

	    /*
	     * Remaining LEAF cases may involve filling Tcl_Tokens, so
	     * make room for at least 2 more tokens.
	     */

	    if (parsePtr->numTokens+1 >= parsePtr->tokensAvailable) {
		TclExpandTokenArray(parsePtr);
	    }
	    wordIndex = parsePtr->numTokens;
	    tokenPtr = parsePtr->tokenPtr + wordIndex;
	    tokenPtr->type = TCL_TOKEN_WORD;
	    tokenPtr->start = start;
	    parsePtr->numTokens++;

	    switch (lexeme) {
	    case QUOTED:
		code = Tcl_ParseQuotedString(interp, start, numBytes,
			parsePtr, 1, &end);








		scanned = end - start;
		break;

	    case BRACED:
		code = Tcl_ParseBraces(interp, start, numBytes,
			    parsePtr, 1, &end);



		scanned = end - start;
		break;

	    case VARIABLE:
		code = Tcl_ParseVarName(interp, start, numBytes, parsePtr, 1);

		/*

		 * Handle the quirk that Tcl_ParseVarName reports a successful
		 * parse even when it gets only a "$" with no variable name.


		 */

		tokenPtr = parsePtr->tokenPtr + wordIndex + 1;
		if (code == TCL_OK && tokenPtr->type != TCL_TOKEN_VARIABLE) {
		    TclNewLiteralStringObj(msg, "invalid character \"$\"");
		    code = TCL_ERROR;
		    continue;
		}
		scanned = tokenPtr->size;
		break;

			code = TCL_ERROR;
			break;
		    }
		}
		TclStackFree(interp, nestedPtr);
		end = start;
		start = tokenPtr->start;








		scanned = end - start;
		tokenPtr->size = scanned;
		parsePtr->numTokens++;
		break;
	    }
	    }
	    if (code != TCL_OK) {
		/*
		 * Here we handle all the syntax errors generated by
		 * the Tcl_Token generating parsing routines called in the
		 * switch just above.  If the value of parsePtr->incomplete
		 * is 1, then the error was an unbalanced '[', '(', '{',
		 * or '"' and parsePtr->term is pointing to that unbalanced
		 * character.  If the value of parsePtr->incomplete is 0,
		 * then the error is one of lacking whitespace following a
		 * quoted word, for example: expr {[an error {foo}bar]},
		 * and parsePtr->term points to where the whitespace is
		 * missing.  We reset our values of start and scanned so that
		 * when our error message is constructed, the location of
		 * the syntax error is sure to appear in it, even if the
		 * quoted expression is truncated.
		 */
		start = parsePtr->term;
		scanned = parsePtr->incomplete;
		/* Escape the parse loop to report the syntax error. */
		continue;
	    }

	    tokenPtr = parsePtr->tokenPtr + wordIndex;
	    tokenPtr->size = scanned;
	    tokenPtr->numComponents = parsePtr->numTokens - wordIndex - 1;
	    if (!parseOnly && ((lexeme == QUOTED) || (lexeme == BRACED))) {