crystal/step1_read_print.cr

   1 #! /usr/bin/env crystal run
   2
   3 require "./readline"
   4 require "./reader"
   5 require "./printer"
   6
   7 # Note:
   8 # Employed downcase names because Crystal prohibits uppercase names for methods
   9
  10 module Mal
  11   extend self
  12
  13   def read(str)
  14     read_str str
  15   end
  16
  17   def eval(x)
  18       x
  19   end
  20
  21   def print(result)
  22     pr_str(result, true)
  23   end
  24
  25   def rep(str)
  26     print(eval(read(str)))
  27   end
  28 end
  29
  30 while line = my_readline("user> ")
  31   begin
  32     puts Mal.rep(line)
  33   rescue e
  34     STDERR.puts e
  35   end
  36 end