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%{
#define _XOPEN_SOURCE 700
#include <locale.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>

#include "expr.h"

#include "y.tab.h"

extern int yyparse(void);

%}

DIGIT [0-9]

%%

"|"	return OR;
"&"	return AND;
"="	return COMPARISON;
">"	return COMPARISON;
">="	return COMPARISON;
"<"	return COMPARISON;
"<="	return COMPARISON;
"!="	return COMPARISON;
"+"	return '+';
"-"	return '-';;
"*"	return MULTIPLICATION;
"/"	return MULTIPLICATION;
"%"	return MULTIPLICATION;
"("	return '(';
")"	return ')';
":"	return MATCH;
{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		;

%%

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;
	}

	size_t n = 1;
	for (int i = optind; i < argc; i++) {
		n += strlen(argv[i]) + 1;
	}

	FILE *mem = fmemopen(NULL, n, "w+");
	for (int i = optind; i < argc; i++) {
		fprintf(mem, "%s\n", argv[i]);
	}
	rewind(mem);

	yyin = mem;

	return yyparse();
}