1 files changed, 87 insertions, 0 deletions
diff --git a/libs/cassowary/ClReader.l b/libs/cassowary/ClReader.l
new file mode 100644
index 0000000000..77fa13a5a1
--- /dev/null
+++ b/libs/cassowary/ClReader.l
@@ -0,0 +1,87 @@
+/* $Id$
+ Cassowary Incremental Constraint Solver
+ Original Smalltalk Implementation by Alan Borning
+ This C++ Implementation by Greg J. Badros, <gjb@cs.washington.edu>
+ http://www.cs.washington.edu/homes/gjb
+ (C) 1998, 1999 Greg J. Badros and Alan Borning
+ See ../LICENSE for legal details regarding this software
+
+ ClReader.l - Scanner for constraint parsing.
+ By Greg J. Badros
+ */
+
+%{
+/* Get the token numbers that bison created for us
+   (uses the -d option of bison) */
+
+#include <cassowary/ClReader.h>
+#include "ClReader.cc.h"
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#define CONFIG_H_INCLUDED
+#endif
+
+/* global variable for the istream we are reading from;
+   gets set by PcnParseConstraint */
+istream *pxi_lexer;
+
+/* Pass in an extra variable (ClParseData *) to cllex so that
+   it can look up variable names */
+#define YY_DECL int cllex(YYSTYPE *lvalp, void *YYLEX_PARAM)
+
+/* Make lexer reader from the global variable */
+#define YY_INPUT(buf,result,max_size) \
+	 do { if (pxi_lexer->get(buf[0]) && buf[0] > 0) result = 1; \
+		  else result = YY_NULL; } while (0)
+
+%}
+
+%option noyywrap
+
+DIGIT [0-9]
+ALPHA [A-Za-z]
+ALPHANUM [A-Za-z0-9]
+ID_OK_PUNC [-_\[\]]
+RO_ANNOTATION "?"
+ID {ALPHA}({ALPHANUM}|{ID_OK_PUNC})*({RO_ANNOTATION})?
+NUMID "{"{DIGIT}+"}"
+ws [ \t\n]+
+
+%%
+{ws}			/* skip whitespace */
+\n|";"			{ return 0; }
+">="			{ return GEQ; }
+">"			{ return GT; }
+"<=" 			{ return LEQ; }
+"<" 			{ return LT; }
+"==" 			{ return '='; }
+"="|"-"|"+"|"*"|"/"|"("|")" 	{ return yytext[0]; }
+
+{DIGIT}+("."{DIGIT}*)? |
+"."{DIGIT}+		{ lvalp->num = strtod(yytext,0); return NUM; }
+
+{ID} 			{       /* Lookup the variable name */
+      ClParseData *pclpd = ((ClParseData *) YYLEX_PARAM);
+      int cch = strlen(yytext);
+      ClVariable *pclv = NULL;
+      bool fReadOnly = false;
+      if (yytext[cch-1] == '?') {
+	yytext[cch-1] = '\0';
+	fReadOnly = true;
+      }
+      const string str = string(yytext);
+      pclv = pclpd->_lookup_func(str);
+      if (!pclv->IsNil()) {
+        lvalp->pclv = pclv;
+        return fReadOnly?RO_VAR:VAR;
+      } else {
+	pxi_lexer = NULL;
+	yy_flush_buffer(YY_CURRENT_BUFFER);
+	throw ExCLParseErrorBadIdentifier(str);
+        return 0;
+      }
+   }
+
+.     {	pxi_lexer = NULL; throw ExCLParseErrorMisc("Unrecognized character"); }
+