Re: How can I sort my array numerically on part of the string?

I don't like this as much as your hash approach which has appeal, but this seems to work:


my @sorted = sort byPrefix @s;



# sort the keys numerically
sub byPrefix {

# make copies so originals are preserved
  my ( $x, $y ) = ( $a, $b );

# get prefixes
  $x =~ s/:.+//;
  $y =~ s/:.+//;

# RV
  $_=0;
  $x < $y && $_--;
  $x > $y && $_++;
  $_;
}
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Comment on Re: How can I sort my array numerically on part of the string? Download Code

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Re^2: How can I sort my array numerically on part of the string? by AnomalousMonk (Archbishop) on Dec 01, 2020 at 21:55 UTC
`$_=0;` Shouldn't this be `local $_ = 0;` to avoid global variable side effects (see local)? `$_=0; $x < $y && $_--; $x > $y && $_++; $_;` [download] And how does this code differ in effect from `$x <=> $y;` (see `<=>` in Equality Operators in perlop)? (And a small point, but , (comma) is used as the delimiter in the OPed example data instead of : (colon), which you use in the `s/:.+//` extraction substitutions.) Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]

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Re^2: How can I sort my array numerically on part of the string?
by AnomalousMonk (Archbishop) on Dec 01, 2020 at 21:55 UTC

$_=0;

Shouldn't this be
local $_ = 0;
to avoid global variable side effects (see local)?

$_=0; $x < $y && $_--; $x > $y && $_++; $_;
[download]

And how does this code differ in effect from
$x <=> $y;
(see <=> in Equality Operators in perlop)?

(And a small point, but , (comma) is used as the delimiter in the OPed example data instead of : (colon), which you use in the s/:.+// extraction substitutions.)

Give a man a fish: <%-{-{-{-<

[reply]
[d/l]
[select]