Changeset 6926

Timestamp:

09/10/05 21:49:40 (3 years ago)

Author:

iblech

Message:

* t/var/autoderef.t: Refs to subrefs should not autoderef.
* pugs::run: Added short paragraph about the features of our backends.
* PIL2JS: README: Added section about the implementation of laziness.

Files:

• lib/pugs/run.pod (modified) (1 diff)
• perl5/PIL2JS/README (modified) (1 diff)
• t/var/autoderef.t (modified) (5 diffs)

lib/pugs/run.pod

@@ -72 +72 @@
 backends are C<Parrot> and C<PIR>.
 
-The JavaScript backend provides an interactive shell in
+The JavaScript backend (PIL2JS) provides an interactive shell in
 F<perl5/PIL2JS/jspugs.pl>; The interactive compiler and evaluator of the Perl 5
-backend can be found in F<perl5/PIL-Run/crude_repl.pl>.
+backend (PIL-Run) can be found in F<perl5/PIL-Run/crude_repl.pl>.
+
+The normal runcore supports more features than the other runcores, the Parrot
+backend is quite fast, PIL2JS is good on binding and references, and PIL-Run
+offers excellent support for laziness.
 
 =item C<-CI<backend>>

perl5/PIL2JS/README

@@ -479 +479 @@
 =back
 
+=head2 Laziness
+
+=head3 C<lazy {...}>
+
+PIL2JS fully supports nothingmuch's accepted C<lazy {...}> proposal (see
+F<t/var/lazy.t>). Only one real problem arose during implementing C<&lazy>:
+C<.FETCH> is called very often, for example at sub return (because of
+C<PIL2JS.Box.ReadOnly>). Therefore, C<&lazy>'s current implementation does not
+return the lazy value directly, but an autodereffing reference to it. This way
+the body is only called when it is really needed.
+
+=head3 Lazy lists
+
+Lazy lists aren't supported at all yet, you may want to look at PIL-Run if you
+want to experiment with lazy lists.
+
 =head1 JAVASCRIPT RUNTIME ENVIRONMENTS
 

t/var/autoderef.t

@@ -7 +7 @@
 # http://www.nntp.perl.org/group/perl.perl6.language/22532.
 
-plan 18;
+plan 22;
 
+# Refs to "non-objects" (in this case, a number) should not autoderef.
 {
   my $x = 3;
@@ -21 +22 @@
 }
 
+# Refs to "objects" (in this case, an array) should autoderef.
 {
   my @x = (1,2,3);
@@ -34 +36 @@
 }
 
+# Refs to "objects" (in this case, a hash) should autoderef.
 {
   my %x = (:a(1), :b(2), :c(3));
@@ -47 +50 @@
 }
 
+# Refs to "non-objects" (in this case, a ref) should not autoderef.
 {
   my @x = (1,2,3);
@@ -53 +57 @@
 
   ok !$z.isa("Array"), "refs to Refs should not autoderef", :todo<bug>;
-  dies_ok { +$z },     "refs to Refs don't numify", :todo<bug>;
-  dies_ok { ~$z },     "refs to Refs don't stringify", :todo<bug>;
+  dies_ok { +$z },     "refs to Refs don't numify (1)", :todo<bug>;
+  dies_ok { ~$z },     "refs to Refs don't stringify (1)", :todo<bug>;
 
   @x = ();
-  ok ?$z, "refs to Refs always booleanify to true", :todo<bug>;
+  ok ?$z, "refs to Refs always booleanify to true (1)", :todo<bug>;
+}
+
+# Refs to "non-objects" (in this case, a subref) should not autoderef.
+{
+  my $x = { 42 };
+  my $y = \$x;
+
+  ok !$y.isa("Code"), "refs to subrefs should not autoderef", :todo<bug>;
+  dies_ok { +$y },    "'real refs' don't numify (2)";
+  dies_ok { ~$y },    "'real refs' don't stringify (2)", :todo<bug>;
+
+  $x = undef;
+  ok ?$y, "'real refs' always booleanify to true (2)";
 }