#include <stdio.h>
#include <ctype.h>
#include "exprParser.h"

int tokenVal,currentToken;

void getToken()
{
    int c,n;
again:
    c = getc(stdin);
    switch(c){
    case '+': 
	currentToken = PLUS_OP;
	return;
    case '-': 
	currentToken = MINUS_OP;
	return;
    case '\n': 
	currentToken = EOL;
	return;
    }
    if(isspace(c)) goto again;
    if(isdigit(c)){
	n = 0;
	do {
	    n = n*10 + c - '0';
	    c = getc(stdin);
	} while(isdigit(c));
	ungetc(c,stdin);
	tokenVal = n;
	currentToken = NUM;
	return;
    }
    fprintf(stderr,"bad char '%c'\n",c);
    exit(1);
}