c/step0_repl.c

   1 #include <stdlib.h>
   2 #include <stdio.h>
   3 #include <unistd.h>
   4
   5 #ifdef USE_READLINE
   6   #include <readline/readline.h>
   7   #include <readline/history.h>
   8 #else
   9   #include <editline/readline.h>
  10 #endif
  11
  12 char *READ(char prompt[]) {
  13     char *line;
  14     line = readline(prompt);
  15     if (!line) return NULL; // EOF
  16     add_history(line); // Add input to history.
  17     return line;
  18 }
  19
  20 char *EVAL(char *ast, void *env) {
  21     return ast;
  22 }
  23
  24 char *PRINT(char *exp) {
  25     return exp;
  26 }
  27
  28 int main()
  29 {
  30     char *ast, *exp;
  31     char prompt[100];
  32
  33     // Set the initial prompt
  34     snprintf(prompt, sizeof(prompt), "user> ");
  35
  36     for(;;) {
  37         ast = READ(prompt);
  38         if (!ast) return 0;
  39         exp = EVAL(ast, NULL);
  40         g_print("%s\n", PRINT(exp));
  41
  42         free(ast); // Free input string
  43     }
  44 }