Re: Indirect method invocation

On Jul 27, 2005, at 17:21, Jan Eden wrote:

My other problem is that the cookbook quotes (something like) the following code as an example for storing method names:

my %actions = (
display => $item->display(),
move_picture => $item->move_picture($item->{id}, $item-> {parameters}->{position}),
commit => $item->commit()
);

Are you sure? $item->display() returns whatever the display() method returns, which might be a coderef, but looks unlikely.

Since you can't get a reference to a method (bound to an instance) as you do with regular subroutines, the technique normally is to wrap them in an anonyomus closure like this:

    package Foo;

    sub new { bless {}, shift }
    sub method { print "Moo!" }

    package main;

    my $foo = Foo->new;
    my %actions = (foo => sub { $foo->method(@_) } );
    $actions{foo}(); # prints "Moo!"

-- fxn


.

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