X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FSafe%2FIsa.pm;h=1616687ee5b8fa6deb324967decea331be39b518;hb=ad7bcdc0922f35703817dda63c6b414c90fbd74a;hp=47cfd3e9e3d29aa61570732e13ca9c04807e3ee8;hpb=b19500dfa77d52b512241b8a75693636241c4c14;p=p5sagit%2FSafe-Isa.git diff --git a/lib/Safe/Isa.pm b/lib/Safe/Isa.pm index 47cfd3e..1616687 100644 --- a/lib/Safe/Isa.pm +++ b/lib/Safe/Isa.pm @@ -2,19 +2,20 @@ 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 = '1.000005'; +our $VERSION = '1.000007'; -our @EXPORT = qw($_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(@_); }; @@ -23,6 +24,11 @@ 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); + $obj->$_call_if_object(can => $method) && $obj->$_call_if_object($method => @_); +}; + 1; __END__ @@ -71,9 +77,10 @@ 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: @@ -153,6 +160,14 @@ 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