46 lines
961 B
Plaintext
46 lines
961 B
Plaintext
|
%token_type {int}
|
||
|
|
|
||
|
|
%left PLUS MINUS.
|
||
|
|
%left DIVIDE TIMES.
|
||
|
|
|
||
|
|
%include {
|
||
|
|
#include <stdio.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <assert.h>
|
||
|
|
#include "calculator-c.h"
|
||
|
|
}
|
||
|
|
|
||
|
|
%code {
|
||
|
|
int main()
|
||
|
|
{
|
||
|
|
void* pParser = ParseAlloc(malloc);
|
||
|
|
ParseTrace(stderr, "> ");
|
||
|
|
Parse(pParser, INTEGER, 1);
|
||
|
|
Parse(pParser, PLUS, 0);
|
||
|
|
Parse(pParser, INTEGER, 2);
|
||
|
|
Parse(pParser, TIMES, 0);
|
||
|
|
Parse(pParser, INTEGER, 10);
|
||
|
|
Parse(pParser, DIVIDE, 0);
|
||
|
|
Parse(pParser, INTEGER, 2);
|
||
|
|
Parse(pParser, 0, 0);
|
||
|
|
ParseFree(pParser, free);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
%syntax_error {
|
||
|
|
fprintf(stderr, "Syntax error\n");
|
||
|
|
}
|
||
|
|
|
||
|
|
program ::= expr(A). { printf("Result=%d\n", A); }
|
||
|
|
expr(A) ::= expr(B) MINUS expr(C). { A = B - C; }
|
||
|
|
expr(A) ::= expr(B) PLUS expr(C). { A = B + C; }
|
||
|
|
expr(A) ::= expr(B) TIMES expr(C). { A = B * C; }
|
||
|
|
expr(A) ::= expr(B) DIVIDE expr(C). {
|
||
|
|
if (C != 0) {
|
||
|
|
A = B / C;
|
||
|
|
} else {
|
||
|
|
fprintf(stderr, "Divide by zero\n");
|
||
|
|
}
|
||
|
|
}
|
||
|
|
expr(A) ::= INTEGER(B). { A = B; }
|