| 1 | use strict; |
| 2 | use warnings FATAL => qw(all); |
| 3 | no if $] >= 5.018, warnings => "experimental::smartmatch"; |
| 4 | use File::Basename; |
| 5 | use lib dirname (__FILE__); |
| 6 | use readline qw(mal_readline set_rl_mode); |
| 7 | use feature qw(switch); |
| 8 | use Data::Dumper; |
| 9 | |
| 10 | use types qw($nil $true $false _list_Q); |
| 11 | use reader; |
| 12 | use printer; |
| 13 | use env; |
| 14 | use core qw($core_ns); |
| 15 | |
| 16 | # read |
| 17 | sub READ { |
| 18 | my $str = shift; |
| 19 | return reader::read_str($str); |
| 20 | } |
| 21 | |
| 22 | # eval |
| 23 | sub eval_ast { |
| 24 | my($ast, $env) = @_; |
| 25 | given (ref $ast) { |
| 26 | when (/^Symbol/) { |
| 27 | $env->get($ast); |
| 28 | } |
| 29 | when (/^List/) { |
| 30 | my @lst = map {EVAL($_, $env)} @{$ast->{val}}; |
| 31 | return List->new(\@lst); |
| 32 | } |
| 33 | when (/^Vector/) { |
| 34 | my @lst = map {EVAL($_, $env)} @{$ast->{val}}; |
| 35 | return Vector->new(\@lst); |
| 36 | } |
| 37 | when (/^HashMap/) { |
| 38 | my $new_hm = {}; |
| 39 | foreach my $k (keys( %{ $ast->{val} })) { |
| 40 | $new_hm->{$k} = EVAL($ast->get($k), $env); |
| 41 | } |
| 42 | return HashMap->new($new_hm); |
| 43 | } |
| 44 | default { |
| 45 | return $ast; |
| 46 | } |
| 47 | } |
| 48 | } |
| 49 | |
| 50 | sub EVAL { |
| 51 | my($ast, $env) = @_; |
| 52 | |
| 53 | while (1) { |
| 54 | |
| 55 | #print "EVAL: " . printer::_pr_str($ast) . "\n"; |
| 56 | if (! _list_Q($ast)) { |
| 57 | return eval_ast($ast, $env); |
| 58 | } |
| 59 | |
| 60 | # apply list |
| 61 | my ($a0, $a1, $a2, $a3) = @{$ast->{val}}; |
| 62 | given ((ref $a0) =~ /^Symbol/ ? $$a0 : $a0) { |
| 63 | when (/^def!$/) { |
| 64 | my $res = EVAL($a2, $env); |
| 65 | return $env->set($a1, $res); |
| 66 | } |
| 67 | when (/^let\*$/) { |
| 68 | my $let_env = Env->new($env); |
| 69 | for(my $i=0; $i < scalar(@{$a1->{val}}); $i+=2) { |
| 70 | $let_env->set($a1->nth($i), EVAL($a1->nth($i+1), $let_env)); |
| 71 | } |
| 72 | $ast = $a2; |
| 73 | $env = $let_env; |
| 74 | # Continue loop (TCO) |
| 75 | } |
| 76 | when (/^do$/) { |
| 77 | eval_ast($ast->slice(1, $#{$ast->{val}}-1), $env); |
| 78 | $ast = $ast->nth($#{$ast->{val}}); |
| 79 | # Continue loop (TCO) |
| 80 | } |
| 81 | when (/^if$/) { |
| 82 | my $cond = EVAL($a1, $env); |
| 83 | if ($cond eq $nil || $cond eq $false) { |
| 84 | $ast = $a3 ? $a3 : $nil; |
| 85 | } else { |
| 86 | $ast = $a2; |
| 87 | } |
| 88 | # Continue loop (TCO) |
| 89 | } |
| 90 | when (/^fn\*$/) { |
| 91 | return Function->new(\&EVAL, $a2, $env, $a1); |
| 92 | } |
| 93 | default { |
| 94 | my $el = eval_ast($ast, $env); |
| 95 | my $f = $el->nth(0); |
| 96 | if ((ref $f) =~ /^Function/) { |
| 97 | $ast = $f->{ast}; |
| 98 | $env = $f->gen_env($el->rest()); |
| 99 | # Continue loop (TCO) |
| 100 | } else { |
| 101 | return &{ $f }($el->rest()); |
| 102 | } |
| 103 | } |
| 104 | } |
| 105 | |
| 106 | } # TCO while loop |
| 107 | } |
| 108 | |
| 109 | # print |
| 110 | sub PRINT { |
| 111 | my $exp = shift; |
| 112 | return printer::_pr_str($exp); |
| 113 | } |
| 114 | |
| 115 | # repl |
| 116 | my $repl_env = Env->new(); |
| 117 | sub REP { |
| 118 | my $str = shift; |
| 119 | return PRINT(EVAL(READ($str), $repl_env)); |
| 120 | } |
| 121 | |
| 122 | # core.pl: defined using perl |
| 123 | foreach my $n (%$core_ns) { |
| 124 | $repl_env->set(Symbol->new($n), $core_ns->{$n}); |
| 125 | } |
| 126 | $repl_env->set(Symbol->new('eval'), sub { EVAL($_[0]->nth(0), $repl_env); }); |
| 127 | my @_argv = map {String->new($_)} @ARGV[1..$#ARGV]; |
| 128 | $repl_env->set(Symbol->new('*ARGV*'), List->new(\@_argv)); |
| 129 | |
| 130 | # core.mal: defined using the language itself |
| 131 | REP("(def! not (fn* (a) (if a false true)))"); |
| 132 | REP("(def! load-file (fn* (f) (eval (read-string (str \"(do \" (slurp f) \")\")))))"); |
| 133 | |
| 134 | if (scalar(@ARGV) > 0 && $ARGV[0] eq "--raw") { |
| 135 | set_rl_mode("raw"); |
| 136 | shift @ARGV; |
| 137 | } |
| 138 | if (scalar(@ARGV) > 0) { |
| 139 | REP("(load-file \"" . $ARGV[0] . "\")"); |
| 140 | exit 0; |
| 141 | } |
| 142 | while (1) { |
| 143 | my $line = mal_readline("user> "); |
| 144 | if (! defined $line) { last; } |
| 145 | do { |
| 146 | local $@; |
| 147 | my $ret; |
| 148 | eval { |
| 149 | use autodie; # always "throw" errors |
| 150 | print(REP($line), "\n"); |
| 151 | 1; |
| 152 | } or do { |
| 153 | my $err = $@; |
| 154 | given (ref $err) { |
| 155 | when (/^BlankException/) { |
| 156 | # ignore and continue |
| 157 | } |
| 158 | default { |
| 159 | chomp $err; |
| 160 | print "Error: $err\n"; |
| 161 | } |
| 162 | } |
| 163 | }; |
| 164 | }; |
| 165 | } |