yorick/step1_read_print.i

   1 set_path, get_env("YORICK_MAL_PATH") + ":" + get_path()
   2 require, "reader.i"
   3 require, "printer.i"
   4
   5 func READ(str)
   6 {
   7   return read_str(str)
   8 }
   9
  10 func EVAL(exp, env)
  11 {
  12   if (structof(exp) == MalError) return exp
  13   return exp
  14 }
  15
  16 func PRINT(exp)
  17 {
  18   if (structof(exp) == MalError) return exp
  19   return pr_str(exp, 1)
  20 }
  21
  22 func REP(str)
  23 {
  24   return PRINT(EVAL(READ(str), ""))
  25 }
  26
  27 func main(void)
  28 {
  29   stdin_file = open("/dev/stdin", "r")
  30   while (1) {
  31     write, format="%s", "user> "
  32     line = rdline(stdin_file, prompt="")
  33     if (!line) break
  34     if (strlen(line) > 0) {
  35       result = REP(line)
  36       if (structof(result) == MalError) write, format="Error: %s\n", result.message
  37       else write, format="%s\n", result
  38     }
  39   }
  40   write, ""
  41 }
  42
  43 main;