1 files changed, 111 insertions, 5 deletions
diff --git a/expr.y b/expr.y
index b2f2061..f409c5c 100644
--- a/expr.y
+++ b/expr.y
@@ -1,16 +1,27 @@
 %{
+#define _XOPEN_SOURCE 700
+#include <locale.h>
+#include <string.h>
 #include <stdio.h>
 #include <stdlib.h>
-#include <string.h>
+#include <unistd.h>
+#include <inttypes.h>
+
+typedef struct {
+	int type;
+	union {
+		intmax_t i;
+		char *s;
+	} u;
+} expr_yystype;
+
+#define YYSTYPE expr_yystype
 
-#include "expr.h"
 #include "y.tab.h"
 
-extern int yylex(void);
+static int yylex(void);
 extern int yyerror(const char *s);
 
-static void breakpoint(void) { }
-
 static void expr_only_integers(YYSTYPE *y1, YYSTYPE *y2)
 {
 	if (y1->type == STRING) {
@@ -140,3 +151,98 @@ expr	: STRING {
 		printf("or\n");
 	}
 	;
+
+%%
+
+
+/*
+
+"|"	return '|';
+"&"	return '&';
+"="	return '=';
+">"	return '>';
+">="	return GE;
+"<"	return '<';
+"<="	return LE;
+"!="	return NE;
+"+"	return '+';
+"-"	return '-';
+"*"	return '*';
+"/"	return '/';
+"%"	return '%';
+"("	return '(';
+")"	return ')';
+":"	return ':';
+{DIGIT}+	{ yylval.u.i = atoi(yytext); return yylval.type = INTEGER; }
+-{DIGIT}+	{ yylval.u.i = atoi(yytext); return yylval.type = INTEGER; }
+.+		{ yylval.u.s = strdup(yytext); return yylval.type = STRING; }
+\n		;
+
+*/
+
+static char **expr_args;
+
+static int yylex(void)
+{
+	if (expr_args[optind] == NULL) {
+		return YYEOF;
+	}
+
+	char *s = expr_args[optind];
+
+	if (strlen(s) == 1) {
+		char c = s[0];
+		if (strchr("|&=+-*/%():", c)) {
+			optind++;
+			return c;
+		}
+	}
+
+	if (strlen(s) == 2) {
+		if (!strcmp(s, ">=")) {
+			optind++;
+			return GE;
+		}
+		if (!strcmp(s, "<=")) {
+			optind++;
+			return LE;
+		}
+		if (!strcmp(s, "!=")) {
+			optind++;
+			return NE;
+		}
+	}
+
+	char *end = NULL;
+	yylval.type = INTEGER;
+	yylval.u.i = strtoimax(s, &end, 10);
+	if (end && *end != '\0') {
+		yylval.type = STRING;
+		yylval.u.s = s;
+	}
+
+	optind++;
+	return yylval.type;
+}
+
+int main(int argc, char *argv[])
+{
+	setlocale(LC_ALL, "");
+
+	int c;
+	while ((c = getopt(argc, argv, "")) != -1) {
+		switch (c) {
+		default:
+			return -1;
+		}
+	}
+
+	if (optind >= argc) {
+		fprintf(stderr, "expr: missing operands\n");
+		return 1;
+	}
+
+	expr_args = argv;
+
+	return yyparse();
+}