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Postings from June 2008
On Mon, Jun 02, 2008 at 06:42:59PM +0200, Roland Giersig wrote:
> Abigail wrote:
> >What's the point of changing the meaning of something, and then,
> >when someone uses the new meaning, give a warning the meaning was
> >changed?
>
> Good point. Would it be better to deprecate Fatal (with a warning) and
> tell people to use Fatal::Globally and Fatal::Locally instead? OK,
> forget about that, let's just call ist autodie and be done with it,
> given that we just can remove Fatal from the docs and have autodie take
> its place.
Indeed.
Furthmore, 'autodie' is all lowercased, that is, it looks like a pragma,
and it acts like a pragma in the sense that it is lexically scoped.
'Fatal', however, starts with a uppercase letter, and hence one shouldn't
expect it to behave locally.
> > Who's going to benefit from that?
>
> I was thinking about adding dwimmage to Fatal to "fix" the error-prone
> behaviour. If that is feasible, everybody would benefit from it.
You are assuming here that the current Fatal is error-prone. Do you have
any evidence to back this up?
> >How often do you see people posting code where they used Fatal
> >inside a block, wrongly assuming it would not raise a fatal error outside
> >of the block?
>
> I don't know, do you have any statistics?
I cannot recall ever seeing code where the author used Fatal as if it
had lexical effects.
> What are the consequences of silently making Fatal work on a local scope
> instead of globally? It would make code that before died with a Fatal
> error message now either die at a different location due to some
> undefinedness (which IMHO is acceptable) or just give a warning and
> produce wrong results (which in some cases is not acceptable).
I'd argue that even your first case isn't acceptable:
{use Fatal;}
open my $in, "<", 'does_not_exist';
open my $out, ">", 'does_exists';
print $out <$in>;
This will have wiped out the content of 'something' if you had your way
in changing the semantics of Fatal.
> Is there a way to see if the Fatalized statement is followed by error
> handling code? Am I insane to ask such a question? I think I need a beer...
I think that Pauls approach, leaving Fatal.pm as is and creating a lexically
scoped autodie is the best way.
Abigail