Scalar::Util::Reftype - Alternate reftype() interface
use Scalar::Util::Reftype;
foo() if reftype( "string" )->hash; # foo() will never be called
bar() if reftype( \$var )->scalar; # bar() will be called
baz() if reftype( [] )->array; # baz() will be called
xyz() if reftype( sub {} )->array; # xyz() will never be called
$obj = bless {}, "Foo";
my $rt = reftype( $obj );
$rt->hash; # false
$rt->hash_object; # true
$rt->class; # "Foo"
This document describes version 0.40 of Scalar::Util::Reftype released on 9 September 2009.
This is an alternate interface to Scalar::Util's reftype function. Instead of manual type checking you can just call methods on the result to see if matches the desired type.
Exported by default. EXPR can be any value (even undef).
Returns an object with which you can call various test methods. Unless specified otherwise, all of the test methods return either zero (false) or one (true) based on the EXPR you have specified.
Return values of reftype() can not be used in boolean contexts. If you do, it'll die with a verbose error message.
my $r = reftype( $foo ) || 'something'; # dies bar() if reftype( $foo ); # dies
Always call the test methods on the return value:
bar() if reftype( $foo )->array;
Or, if you want to have multiple tests, without executing reftype multiple times:
my $r = reftype( $foo ); bar() if $r->array; baz() if $r->array_object; die "ooooh! scaaaary..." if $r->format_object;
The available test methods are listed below.
Tests if EXPR is a SCALAR reference or not.
Tests if EXPR is an ARRAY reference or not.
Tests if EXPR is a HASH reference or not.
Tests if EXPR is a CODE reference or not.
Tests if EXPR is a GLOB reference or not.
Tests if EXPR is a LVALUE reference or not.
Tests if EXPR is a FORMAT reference or not.
Tests if EXPR is a reference to a reference or not.
Tests if EXPR is a IO reference or not.
CAVEAT: reftype(EXPR)->io_object is also true since there is no way to distinguish them (i.e.: IO refs are already implemented as objects).
Tests if EXPR is a Regexp reference or not.
Tests if EXPR is a SCALAR reference based object or not.
Tests if EXPR is an ARRAY reference based object or not.
Tests if EXPR is a HASH reference based object or not.
Tests if EXPR is a CODE reference based object or not.
Tests if EXPR is a GLOB reference based object or not.
Tests if EXPR is a LVALUE reference based object or not.
Tests if EXPR is a FORMAT reference based object or not.
Tests if EXPR is a reference to a reference based object or not.
Tests if EXPR is a IO reference based object or not.
CAVEAT: reftype(EXPR)->io is also true since there is no way to distinguish them (i.e.: IO refs are already implemented as objects).
Tests if EXPR is a Regexp reference based object or not.
Returns the name of the class the object based on if EXPR is an object. Returns an empty string otherwise.
re::is_regexp to detect if a reference is a regex or not. While it is possible to detect normal regexen in older perls, there is no simple way to detect blessed regexen. Blessing a regex hides it from normal probes. If you are under perl 5.8.x or older, you'll need to install (in fact, it's in the prerequisities list so any automated tool --like cpan shell-- will install it automatically) Data::Dump::Streamer which provides the regex function similar to re::is_regexp.reftype(EXPR)->io and reftype(EXPR)->io_object will return true is EXPR is either and IO reference or an IO reference based object.VSTRING references are not supported and not implemented.FORMAT references can be detected under perl 5.8 and newer. Under older perls, even the accessors are not defined for FORMAT.reftype in Scalar::Utilt/op/ref.t in perl sourceref in perlfunc.Burak Gursoy <burak@cpan.org>.
Copyright 2009 Burak Gursoy. All rights reserved.
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.10.0 or, at your option, any later version of Perl 5 you may have available.
