X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FSafe%2FIsa.pm;h=e6457cf5f56d0b32cb8b19c9557cf265adcb0747;hb=d3136db00d853c6eb60d203f4bc3133abeff6687;hp=206e1dac8d2817a17d790e0e6183842ae4c5338e;hpb=6270ca6fd73f6306a242396da63fd83c646edbde;p=p5sagit%2FSafe-Isa.git diff --git a/lib/Safe/Isa.pm b/lib/Safe/Isa.pm index 206e1da..e6457cf 100644 --- a/lib/Safe/Isa.pm +++ b/lib/Safe/Isa.pm @@ -2,19 +2,19 @@ package Safe::Isa; use strict; use warnings FATAL => 'all'; -use Scalar::Util qw(blessed); +use Scalar::Util (); use Exporter 5.57 qw(import); -our $VERSION = '1.000006'; +our $VERSION = '1.000008'; -our @EXPORT = qw($_call_if_object $_isa $_can $_does $_DOES); +our @EXPORT = qw($_call_if_object $_isa $_can $_does $_DOES $_call_if_can); our $_call_if_object = sub { my ($obj, $method) = (shift, shift); # This is intentionally a truth test, not a defined test, otherwise # we gratuitously break modules like Scalar::Defer, which would be # un-perlish. - return unless blessed($obj); + return unless Scalar::Util::blessed($obj); return $obj->isa(@_) if lc($method) eq 'does' and not $obj->can($method); return $obj->$method(@_); }; @@ -24,6 +24,12 @@ our ($_isa, $_can, $_does, $_DOES) = map { sub { my $obj = shift; $obj->$_call_if_object($method => @_) } } qw(isa can does DOES); +our $_call_if_can = sub { + my ($obj, $method) = (shift, shift); + return unless $obj->$_call_if_object(can => $method); + return $obj->$method(@_); +}; + 1; __END__ @@ -72,9 +78,10 @@ Similarly: $maybe_an_object->$_does('RoleName'); # true or false, no boom today $maybe_an_object->$_DOES('RoleName'); # true or false, no boom today -And just in case we missed a method: +And just in case we missed a method or two: $maybe_an_object->$_call_if_object(name => @args); + $maybe_an_object->$_call_if_can(name => @args); Or to re-use a previous example for purposes of explication: @@ -117,6 +124,9 @@ class names that you might not want to treat as one (like say "Matt") - the C function from L is a good way to check for something you might be able to call methods on if you want to do that. +We are careful to make sure that scalar/list context is preserved for the +method that is eventually called. + =head1 EXPORTS =head2 $_isa @@ -154,6 +164,14 @@ returns nothing. If called on an object, calls C on it and returns the result, otherwise returns nothing. +=head2 $_call_if_can + + $maybe_an_object->$_call_if_can(name => @args); + +If called on an object, calls C on it; if that returns true, then +calls C on it and returns the result; if any condition is false +returns nothing. + =head1 SEE ALSO I gave a lightning talk on this module (and L and L) at