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#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include "basic.h"
static int fg_color = 7, bg_color = 0;
/* Assign a variable a value. */
void assignment()
{
int *var;
int value;
/* get the variable name */
get_token();
if(!isalpha(*token)) {
serror(4);
return;
}
var = find_var(token);
/* get the equals sign */
get_token();
if(*token!='=') {
serror(3);
return;
}
/* get the value to assign to var */
get_exp(&value);
/* assign the value */
*var = value;
}
/* Execute a simple version of the BASIC PRINT statement */
void exec_print()
{
int answer;
int len=0, spaces;
char last_delim;
do {
get_token(); /* get next list item */
if(tok==EOL || tok==FINISHED) break;
if(token_type==QUOTE) { /* is string */
printf("%s", token);
len += strlen(token);
get_token();
}
else { /* is expression */
putback();
get_exp(&answer);
get_token();
len += printf("%d", answer);
}
last_delim = *token;
if(*token==';') {
/* compute number of spaces to move to next tab */
spaces = 8 - (len % 8);
len += spaces; /* add in the tabbing position */
while(spaces) {
printf(" ");
spaces--;
}
}
else if(*token==',') /* do nothing */;
else if(tok!=EOL && tok!=FINISHED) serror(0);
} while (*token==';' || *token==',');
if(tok==EOL || tok==FINISHED) {
if(last_delim != ';' && last_delim!=',') printf("\n");
}
else serror(0); /* error is not , or ; */
}
/* Execute a simple form of the BASIC INPUT command */
void input()
{
int *var;
int tmp;
get_token(); /* see if prompt string is present */
if(token_type==QUOTE) {
printf("%s", token); /* if so, print it and check for comma */
get_token();
if(*token!=',') serror(1);
get_token();
}
else printf("? "); /* otherwise, prompt with / */
var = find_var(token); /* get the input var */
scanf("%d", var); /* read input */
/* flush input */
while ((tmp = getchar()) != '\n' && tmp != EOF);
}
/* COLOR statement */
void color() {
get_exp(&fg_color);
get_token();
if (*token == ',') {
get_exp(&bg_color);
} else if (token_type != DELIMITER) {
serror(0);
}
set_color();
}
void set_color() {
printf("\x1b[%dm\x1b[%dm\x1b[%dm", fg_color % 8 + 30, (fg_color > 7 ? 1 : 22), bg_color % 16 + 40);
}
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