An alternate design is to derive from Foo::Parse.
Interesting approach, but I was specifically interested in callbacks in this case. And -FWIW- in my real world program it's not to be a single sub, but a dispatch table...
Note that $self in the callback doesn't make much sense - it's a Foo::Parse object, and the callback is not a method of Foo::Parse. Better to name it $obj or $fp.
Very good point, in fact I've been lucubrating for a while as for what a good name for what I eventually called $self may have been. Incidentally in my real world program it will be a more descriptive name, like $log, so no problem here. As far as generic use is concerned, $obj is fine IMHO. 
my $fp;
$fp = Foo::Parse->new('FooParser',
  sub {
    local $_ = shift;
    s/^\w+:// or
      $fp->warn("something wrong!");
    split /,/;
  } );

[download]
This makes it into a closure, meaning that $fp remains visible. Even if $fp were itself no longer in scope, this closure can still see it. This is even more normal to me.
Very good point too! I like closures, I just hadn't thought of this possibility...

In reply to Re^2: Seeking advice for OO-related strategy by blazar
in thread Seeking advice for OO-related strategy by blazar

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