Create a multipurpose equal

lib/Minilisp.pm

@@ -104,6 +104,33 @@ sub lisp_format {
     }
 }
 
+sub lisp_equal {
+  my ($a, $b) = @_;
+  if ( ref($a) eq "ARRAY" && ref($b) eq "ARRAY" )
+    {
+      return 0 unless scalar(@$a) == scalar(@$b);
+
+      for(my $i = 0; $i < @$a; $i++)
+        {
+          return 0 unless lisp_equal($a->[$i], $b->[$i]);
+        }
+
+      return 1;
+    }
+  elsif ( ref($a) eq "KEYWORD" && ref($b) eq "KEYWORD" )
+    {
+      return $a->{value} eq $b->{value};
+    }
+  elsif ( ref($a) eq "" && ref($b) eq "" )
+    {
+      return $a == $b;
+    }
+  else
+    {
+      return 0;
+    }
+}
+
 my %stdctx = (
   '+' => sub {
     my $sum = 0;
@@ -259,15 +286,14 @@ my %stdctx = (
     return $v;
   },
   # TODO: this is tricky as it needs to recurse into sub lists
-  'equal' => sub {
-    my ($a, $b) = @_;
-    return @$a == @$b;
-  },
 
   # Constants
   't' => 1,
   'f' => 0,
   'nil' => undef,
+
+  # Multi-purpose
+  'equal' => \&lisp_equal,
 );
 
 sub parser {