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Stylistically, I like this construct of using lexicals for filehandles:1
{ open my $fh, $filename or die "open: $!"; # do somthing with $fh }
I like the economy of declaring the variable just as I'm using it; the fact that it's lexically scoped; how this provides a clean alternative to (global) filehandles.

But what about close? I mean, I know *when* it happens: when $fh goes out of scope. That's the point if this construct. But how does it happen, in terms of error catching? I almost always want to handle errors on close. How do I express that using this syntax? (Where do I hook up my "or die"?)

If choosing this syntax means silent failures in close, it becomes less useful. Maybe there's some declarative way of installing error handlers, a la BASIC ON ERROR or Perl %SIG? Even this starts to be less elegant that I'd hope for, but I can't see another way of expressing it.

Update: Clearly, I can close $fh explicitly when I'm done. But one of the features of this construct is that I can leave the scope in several ways and still have the file close automatically for me.

1 I believe this is relatively new syntax, 5.8-ish or so. Update: turns out it's from 5.6; thanks ikegami.


In reply to Catching errors in closing lexical filehandles by gaal

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