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Re: Comparing decimal values

by BrowserUk (Patriarch)
on Jan 21, 2003 at 17:17 UTC ( [id://228752]=note: print w/replies, xml ) Need Help??


in reply to Comparing decimal values

Concatenating 'v' to the front of each version string and evaling using eq, gt,lt or cmp seems to work okay. I'm sure I saw 'vMMM.nnn.rr' described somewhere in the docs, but I couldn't find it anywhere just now?

#! perl -slw use strict; sub map2 (&@) { use Carp; my $code = shift; croak 'Odd number of values in list' if @_ & 1; map { local ($a, $b) = (shift,shift); $code->() } 1 .. (@_>>1); } sub cmpVer{ eval{'v'.$_[0] cmp 'v'.$_[1];} } # << This is the salient +bit my @a = qw[ 1.1.1 1.1.1 1.1.1 1.1.2 1.1.2 1.1.1 1.1.10 1.2.0 0.111.0 9.0.0 9.0.0 0.111.0 1.4.999 1.5.0 ]; map2{ printf "%10s %2.2s %s\n", $a, (qw/== > </)[cmpVer($a, $b)], $b; } @a; __END__ C:\test>228707 1.1.1 == 1.1.1 1.1.1 < 1.1.2 1.1.2 > 1.1.1 1.1.10 < 1.2.0 0.111.0 < 9.0.0 9.0.0 > 0.111.0 1.4.999 < 1.5.0 C:\test>

If anyone can tell me why I can't supply a qw// list directly to my map2 sub

map2{ print $a, $b; } qw[a b c d];

without getting syntax errors, I'd like to hear the explanation.


Examine what is said, not who speaks.

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