やさしい Lisp の作り方 by Java and by C#を参考に書いてみる。

READ-PRINT-LOOPまでのものを動かしてみる

$ perl moosp.pl 
Moosp> (1 2 3 4)
(1 2 3 4)
Moosp> (e r t)
(E R T)
Moosp> (2 . 3)
(2 . 3)
Moosp> (defun plus (a b) (+ a b))
(DEFUN PLUS (A B) (+ A B))

コード

package Moosp;

use Moose;
use Moosp::Env;
use Moosp::Reader;
use Term::ReadLine;

our $VERSION = 0.01;

sub run {
  my $self = shift;

  my $term = new Term::ReadLine 'Simple LISP REPL';
  my $prompt = "Moosp> ";
  my $OUT = $term->OUT || \*STDOUT;

  while ( defined ($_ = $term->readline($prompt)) ) {
    my $reader = Moosp::Reader->new();
    my $sexp = $reader->readFromString($_);
    warn $@ if $@;
    print $OUT $sexp->serialize(), "\n" unless $@;
  }

}

__PACKAGE__->meta->make_immutable;

no Moose;

1; # End of Moosp

moosp.pl

#!/usr/bin/env perl    
use lib "./lib";    
use Moosp;    
Moosp->new->run();