Author: autrijus
Date: Tue Feb 28 07:22:23 2006
New Revision: 7898
Modified:
doc/trunk/design/syn/S05.pod
Log:
* S05: Generalizing +$/ and ~$/ delegating to $(), by stipulating
that all explicit coercion forms, except for boolean, dispatch
from Match to its result object.
Modified: doc/trunk/design/syn/S05.pod
==============================================================================
--- doc/trunk/design/syn/S05.pod (original)
+++ doc/trunk/design/syn/S05.pod Tue Feb 28 07:22:23 2006
@@ -588,6 +588,17 @@
The closure is guaranteed to be run at the canonical time.
+An B<explicit> return from the closure binds the I<result object> for
+this match, ignores the rest of the current rule, and reports success:
+
+ / (\d) { return $0.sqrt } NotReached /;
+
+This has the effect of capturing the square root of the numified string,
+instead of the string. The C<NotReached> part is not reached.
+
+These closures are invoked as anonymous methods on the C<Match> object.
+See L</Match objects> below for more about result objects.
+
=item *
A leading C<&> interpolates the return value of a subroutine call as
@@ -1115,7 +1126,7 @@
my $moose = m:{
<antler> <body>
- { return Moose.new( body => $<body>().attach($<antler>()) ) }
+ { return Moose.new( body => $<body>().attach($<antler>) ) }
# match succeeds -- ignore the rest of the rule
}.();
@@ -1131,6 +1142,16 @@
In this case the result object is always a string when doing string
matching, and a list of one or more elements when doing array matching.
+Additionally, the C<Match> object delegates its C<coerce> calls
+(such as C<+$match> and C<~$match>) to its underlying result object.
+The only exception is that C<Match> handles boolean coercion itself,
+which returns whether the match had succeeded.
+
+This means that these two work the same:
+
+ / <moose> { $<moose>.() as Moose } /
+ / <moose> { $<moose> as Moose } /
+
=item *
When used as an array, a Match object pretends to be an array of all
