misc/kp6-repl.pl

   1 package RenameMe; #XXX
   2
   3 BEGIN {
   4     chomp(my $lib = `kp6 -lib`);
   5     eval("use lib '$lib';");
   6 }
   7 use KindaPerl6::Runtime::Perl5::Runtime;
   8 use File::Temp 'tmpnam';
   9 use Scriptalicious 1.05;
  10 use strict;
  11
  12 sub call_kp6 {
  13     my($input,$args)=@_;
  14     my $tmpfn = tmpnam();
  15     open(F,"|kp6 $args > $tmpfn") or die;
  16     print F $input;
  17     close(F);
  18     my $output = `cat $tmpfn`;
  19     unlink($tmpfn);
  20     return $output;
  21 }
  22
  23 sub print_repl_help {
  24     print ":h             show this help\n";
  25     print ":q             quit\n";
  26     print ":v             toggles verbose output\n";
  27     print ":5 <p5code>    run perl5 code\n";
  28     print " <p6code>      run perl6 code\n";
  29     print ":l <filename>  run perl6 file\n";
  30 }
  31
  32 # Design issue [Getting-Expression-Value]
  33 # kp6 currently generates p5 code which always evaluates to 1.
  34 # So how should we print the value of the user's expression?
  35 # One can wrap simple expressions in "say".  "say 3;".
  36 # But kp6 doesn't currently understand "{;3}" as a way of
  37 # wrapping expressions without altering scope.
  38 # And wrapping a function and calling it seems likely to
  39 # cause trouble (eg, "sub wrap(){ 3 } say wrap();").
  40 # For now, fudge.
  41
  42 # Design issue [Perserving-Variables]
  43 # kp6 currently uses our() variables, so they are lost at the
  44 # end of the eval(), and unavailable for subsequent user input.
  45 # For now, accumulate all non-error causing p6, and eval the
  46 # entire accumulation.
  47 # We can't accumulate p5 instead of p6, because compilation
  48 # requires knowing previous declarations.
  49 # So the accumulated p6 keeps getting bigger. :(  XXX
  50
  51 my $accumulated_p6; # See [Perserving-Variables].
  52 sub run_repl {
  53     my $verbose = 0;
  54     my $eval_p5 = sub {
  55         my($p5)=@_;
  56         my @result = eval($p5);
  57         print $@ if $@;
  58         # @result is always [1].  See [Getting-Expression-Value].
  59         #print "",(map{defined $_ ? $_ : 'undef'}@result),"\n";
  60     };
  61     my $eval_p6 = sub {
  62         my($p6)=@_;
  63         my $code = $p6;
  64
  65         # XXX Wrap one-liners in say().  See [Getting-Expression-Value].
  66         $code = "say $code;" if $code =~ tr/\n/\n/ <= 1;
  67
  68         # XXX See [Perserving-Variables].
  69         $code = $accumulated_p6 ."\n". $code;
  70         my $new_accumulation = $accumulated_p6 ."\n". $p6;
  71
  72         my $p5 = call_kp6($code,'');
  73         if($verbose) {
  74             print call_kp6($p6,'-ast | perltidy');
  75             print "# p5\n",number_the_lines($p5),"\n";
  76         }
  77         print "----\n";
  78         $eval_p5->($p5);
  79
  80         $accumulated_p6 = $new_accumulation if !$@;
  81     };
  82     print_repl_help();
  83     while (1) {
  84         my $line = prompt_string("p5ugs> ");
  85         last if !defined $line;
  86         if ($line =~ /\A:h\s*\Z/) { print_repl_help(); next;}
  87         if ($line =~ /\A:q\s*\Z/) { exit(0);}
  88         if ($line =~ /\A:v\s*\Z/) { $verbose = !$verbose; next;}
  89         if ($line =~ /\A:5\s+(.+)/) {
  90             $eval_p5->($1);
  91             next;
  92         }
  93         if ($line =~ /\A:l\s+(\S+)/) {
  94             my $filename = $1;
  95             my $p6 = `cat $filename`;
  96             $eval_p6->($p6);
  97             next;
  98         }
  99         $eval_p6->($line);
 100     }
 101 }
 102
 103 sub number_the_lines {
 104     my($s)=@_;
 105     my $cnt = 1;
 106     $s =~ s/^/$cnt++."\t"/mge;
 107     $s;
 108 }
 109
 110 #XXX remove me
 111 run_repl();
 112
 113 1;
 114 __END__