When we memoize methods, get their results lazily to remove some compile-time cost

diff --git a/Changes b/Changes
index 4897d07..1e772d7 100644 (file)
--- a/Changes
+++ b/Changes
@@ -5,6 +5,8 @@ Revision history for Perl extension Class-MOP.
       - Add an "execute" method to invoke the body so
         we can avoid using the coderef overload (Sartak)
     * Class::MOP::Immutable
+      - When we memoize methods, get their results lazily
+        to remove some compile-time cost (Sartak)
       - Small speedup from eliminating several method
         calls (Sartak)
 

diff --git a/lib/Class/MOP/Immutable.pm b/lib/Class/MOP/Immutable.pm
index 58e10c1..3037a1a 100644 (file)
--- a/lib/Class/MOP/Immutable.pm
+++ b/lib/Class/MOP/Immutable.pm
@@ -174,16 +174,6 @@ sub make_metaclass_immutable {
 
         ($metaclass->can($method_name))
             || confess "Could not find the method '$method_name' in " . $metaclass->name;
-
-        if ($type eq 'ARRAY') {
-            $metaclass->{'___' . $method_name} = [ $metaclass->$method_name ];
-        }
-        elsif ($type eq 'HASH') {
-            $metaclass->{'___' . $method_name} = { $metaclass->$method_name };
-        }
-        elsif ($type eq 'SCALAR') {
-            $metaclass->{'___' . $method_name} = $metaclass->$method_name;
-        }
     }
 
     $metaclass->{'___original_class'} = blessed($metaclass);
@@ -267,14 +257,29 @@ sub create_methods_for_immutable_metaclass {
     my $memoized_methods = $self->options->{memoize};
     foreach my $method_name (keys %{$memoized_methods}) {
         my $type = $memoized_methods->{$method_name};
+        my $key = '___' . $method_name;
+        my $method = $meta->find_method_by_name($method_name);
+
         if ($type eq 'ARRAY') {
-            $methods{$method_name} = sub { @{$_[0]->{'___' . $method_name}} };
+            $methods{$method_name} = sub {
+                @{$_[0]->{$key}} = $method->execute($_[0])
+                    if !exists $_[0]->{$key};
+                return @{$_[0]->{$key}};
+            };
         }
         elsif ($type eq 'HASH') {
-            $methods{$method_name} = sub { %{$_[0]->{'___' . $method_name}} };
+            $methods{$method_name} = sub {
+                %{$_[0]->{$key}} = $method->execute($_[0])
+                    if !exists $_[0]->{$key};
+                return %{$_[0]->{$key}};
+            };
         }
         elsif ($type eq 'SCALAR') {
-            $methods{$method_name} = sub { $_[0]->{'___' . $method_name} };
+            $methods{$method_name} = sub {
+                $_[0]->{$key} = $method->execute($_[0])
+                    if !exists $_[0]->{$key};
+                return $_[0]->{$key};
+            };
         }
     }