in reply to Re^2: multiple method calls against the same object (f.ex GUI programming)
in thread multiple method calls against the same object (f.ex GUI programming)

And worse yet, I still need a temporary variable for every widget, even when it's a widget I don't care about having access to later (scrollbars often fall in this category f.ex).
In that case, it gets even easier:
for (Scrollbar->new) { $_->config1($param1); $_->config2($param2); $otherwidget->add($_); }
Don't name anything you don't need to name!

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Re^4: multiple method calls against the same object (f.ex GUI programming)
by Aristotle (Chancellor) on Oct 29, 2002 at 02:16 UTC
    Sorry, one steap ahead of you again. :-) That breaks down when you need to add a nameless widget to another also nameless widget:
    for (HBox->new) { $_->config1($param1); $_->config2($param2); my $sb = Scrollbar->new; for ($sb) { $_->config1($param3); $_->config2($param4); } $_->add($sb); $window->add($_); }

    You need a temporary variable, although at least this one can be tightly scoped.

    It also mingles method calls against several different widgets into a single block, which makes it harder to see what gets added where when. Your proposal is ok on a smaller scale, but scales badly - if you nest several unnamed widgets, it gets messy quick.

    If you look at the tutorial at GtkPerl.org you'll see a really ugly style with lots of variable reuse and calls to different widgets interwoven in a single block. It made my head swim trying to read even the shorter example programs. configure_object was the result of several iterations of refactoring for readability.

    It took enough effort and was beneficial enough that I felt I had to share this.

    Update: Actually I suppose one can coerce the for approach into clean separation by adding some do to the mix:

    $window->add(do { my $hbox = HBox->new; for ($hbox) { $_->config1($param1); $_->config2($param2); $_->add(do { my $sb = Scrollbar->new; for ($sb) { $_->config1($param3); $_->config2($param4); } $sb; }); $hbox; });
    but that's quickly slipping into the realm of cumbersome. I really spent some serious time trying to get this whole deal to look reasonably readable, and no conventional tools would help, hence the snippet.

    Makeshifts last the longest.