Re: Are common access expressions optimized?

No, it doesn't. Perl's "optimizer" is really pretty dim. The best you can do for exists tests is

my $very_deep_nested = $very->{deeply}{nested};
$very_deeply_nested->{hash} = $something
   unless exists $very_deeply_nested->{hash};
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or as I prefer,

exists $_->{hash} and $_->{hash} = $something
    for $very->{deeply}{nested};
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Makeshifts last the longest.

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Re: Re: Are common access expressions optimized? by John M. Dlugosz (Monsignor) on Dec 23, 2002 at 16:20 UTC
Thanks. I'm looking forward to "given" in Perl 6. I thought about that yesterday when I had a similar temporary that was only needed for the next two lines. Emulating with a one-iteration foreach is probably too obtuse.	[reply]
Re^3: Are common access expressions optimized? by Aristotle (Chancellor) on Dec 23, 2002 at 16:34 UTC
It's what Larry advertises. `:)` (Look for `Topicalization`.) I don't think it's obtuse at all - you might be surprised the first time you see it, but did you really have any problem reading it? I think it's immediately obvious what is happening. Makeshifts last the longest.	[reply]
Re: Re: Are common access expressions optimized? by paulbort (Hermit) on Dec 24, 2002 at 19:05 UTC
Aristotle, Thank you; I now have a better understanding of the word sublime. That's high art. I'm going to go read the LW link in your other reply now. -- Spring: Forces, Coiled Again!	[reply]