Perl: add step1_read_print, types.

1 files changed, 33 insertions, 0 deletions

diff --git a/perl/printer.pm b/perl/printer.pm
new file mode 100644
index 0000000..9741eda
--- /dev/null
+++ b/perl/printer.pm
@@ -0,0 +1,33 @@
+package printer;
+use feature qw(switch);
+use strict;
+use warnings;
+use Exporter 'import';
+our @EXPORT_OK = qw( _pr_str );
+
+use types qw($nil $true $false);
+
+sub _pr_str {
+    my($obj) = @_;
+    given (ref $obj) {
+        when(/^List/) {
+            return '(' . join(' ', map {_pr_str($_)} @$obj) . ')';
+        }
+        when(/^Vector/) {
+            return '[' . join(' ', map {_pr_str($_)} @$obj) . ']';
+        }
+        when(/^HashMap/) {
+            my @elems = ();
+            foreach my $key (keys %$obj) {
+                push(@elems, _pr_str(String->new($key)));
+                push(@elems, _pr_str($obj->{$key}));
+            }
+
+            return '{' . join(' ', @elems) . '}';
+        }
+        when(/^String/) { return '"' . $$obj . '"'; }
+        default         { return $$obj; }
+    }
+}
+
+1;