Re^2: Deleting specific element in array in FOREACH loop

for my $index (reverse 0 .. $#array)
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is a more Perlish way to achieve that. It is clearer and avoids fence posts.

DWIM is Perl's answer to Gödel

Comment on Re^2: Deleting specific element in array in FOREACH loop Download Code

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Re^3: Deleting specific element in array in FOREACH loop by ikegami (Patriarch) on Sep 15, 2006 at 20:08 UTC
The downside is that `for my $index (reverse 0 .. $#array)` creates a list as large as the array, whereas `for (my $i = $#array; $i > -1; $i--)` and `for (my $i = @array; $i--; )` have no memory cost. That said, it usually doesn't matter. On the plus side, `for my $index (reverse 0 .. $#array)` could be slower. It is optimized to loop backwards instead of actually calling `reverse`.	[reply] [d/l] [select]
Re^4: Deleting specific element in array in FOREACH loop by mreece (Friar) on Sep 15, 2006 at 20:15 UTC
for modern versions of perl, this is no longer true for normal ranges. does it still create the array for 'reverse' ranges?	[reply]
Re^5: Deleting specific element in array in FOREACH loop by ikegami (Patriarch) on Sep 15, 2006 at 21:47 UTC
Yes. In perl 5.8.6+, the `reverse` is optimized away, but the range is still flattened. I don't see anything in the perl588delta which says this has since changed. See lidden's Re^5: the '..' operator and decreasing values.	[reply] [d/l]