Re: Concatenate and join

Another solution (TIMTOWTDI), using pack and unpack:

#!/usr/bin/perl
use warnings;
use strict;

my $mac_address = '28:8a:1c:59:cc:85';
$mac_address =~ tr/://d;
print join '.', unpack '(H4)*', pack 'H*', $mac_address;
[download]

Update: Could anyone use pack to skip the colons, without the need to remove them beforehand?

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
[download]

Comment on Re: Concatenate and join Select or Download Code

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Re^2: Concatenate and join by Marshall (Canon) on Mar 31, 2016 at 14:39 UTC
Interesting. I normally only think of pack and unpack in the context of working with binary buffers, which I seldom do in Perl. While researching regex ideas, I did see your post at Re: Insert colons into a MAC address which is sort of similar to this problem, but I couldn't see how to apply it to leave off the final "." in my regex.	[reply]
Re^3: Concatenate and join by choroba (Cardinal) on Mar 31, 2016 at 14:57 UTC
It's not possible to use the same trick. You want to concatenate the two groups every time, but skip the dot sometimes. Maybe with eval: `s/(\w+):(\w+)(:?)/ $1 . $2 . '.' x !!$3 /ge;` [download] or use two steps (which makes it similar to your solution): `s/(\w+):(\w+)/$1$2/g; tr/:/./;` [download] ($q=q:Sq=~/;[c](.)(.)/;chr(-\|\|-\|5+lengthSq)`"S\|oS2"`map{chr \|+ord }map{substrSq`S_+\|`\|}3E\|-\|`7**2-3:)=~y+S\|`+$1,++print+eval$q,q,a, [download]	[reply] [d/l] [select]