comment on

This is an ongoing theme of mine: see multiple method calls against the same object (f.ex GUI programming) and RFC: Class::Proxy::MethodChain.

I think I have now found an elegant solution I can settle for.

An example similar to the one in multiple method calls against the same object (f.ex GUI programming) would be

my $window = call_on_obj(
    Gtk2::Window->new( "toplevel" ),
    [ signal_connect   => ( delete_event => sub { Gtk2->main_quit } ) 
+],
    [ set_title        => "Test" ],
    [ set_border_width => 15 ],
    [ add              => call_on_obj(
        Gtk2::Button->new( "Quit" ),
        [ signal_connect => ( clicked => sub { Gtk2->main_quit } ) ],
    ) ],
    [ 'show_all' ],
);
[download]

which is equivalent to

my $window = Gtk2::Window->new( "toplevel" );
$window->signal_connect( delete_event => sub { Gtk2->main_quit } );
$window->set_title( "Test" );
$window->set_border_width( 15 );
$window->add( do {
    my $button = Gtk2::Button->new( "Quit" );
    $button->signal_connect( clicked => sub { Gtk2->main_quit } );
    $button;
} );
$window->show_all();
[download]

Update: changed example to actual working Gtk2 code.

Update: fixed re-throw code bug spotted by simonm.

use List::Util;

sub call_on_obj {
    my( $method, @param );
    no warnings 'once';
    List::Util::reduce {
        ( $method, @param ) = @$b;
        eval { $a->$method( @param ) };
        if( $@ ) { { local $@; require Carp; } Carp::croak( $@ ) }
        $a;
    } @_;
}
[download]

In reply to multiple method calls against the same object, revisited by Aristotle

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