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%{
#define _XOPEN_SOURCE 2
#include <locale.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include "expr.h"
%}
DIGIT [0-9]
%%
"|" puts("or");
"&" puts("and");
"=" puts("equal");
">" puts("greater");
">=" puts("greater or equal");
"<" puts("less");
"<=" puts("less or equal");
"!=" puts("not equal");
"+" puts("plus");
"-" puts("minus");
"*" puts("times");
"/" puts("divide");
"%" puts("remainder");
"(" puts("lparen");
")" puts("rparen");
{DIGIT}+ printf("number %s\n", yytext);
-{DIGIT}+ printf("negative %s\n", yytext);
.+ printf("string '%s'\n", yytext);
%%
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]);
}
fprintf(mem, "\n");
rewind(mem);
yyin = mem;
return yylex();
}
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