How do I alphabetize a list of email addresses by domain?

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

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Re: How do I alphabetize a list of email addresses by domain? by Chmrr (Vicar) on Apr 20, 2002 at 07:47 UTC
Wield the Schwartzian Transform for the powers of good: `@sortedEmails = map {$_->[0]} sort {$a->[2] cmp $b->[2]} map {[$_, split /@/]} @emails;` [download] perl -pe '"I lo`+$^X$\"$]!$/"=~m%(.)%s;$_=$1;y^`+*^e v^#$&V"+@( NO CARRIER'	[reply] [d/l]
Re: Re: How do I alphabetize a list of email addresses by domain? by Kanji (Parson) on Apr 20, 2002 at 07:56 UTC
That only sorts `@emails` by domains. To further sort the addresses within each domain, you'd need something like ... `sort { $a->[2] cmp $b->[2] # by domain first, \|\| $a->[1] cmp $b->[1] # then username }` [download] Update: Oops, missed the \|\|. Thanks Chmrr. --k.	[reply] [d/l]
Re: Re: Re: How do I alphabetize a list of email addresses by domain? by Chmrr (Vicar) on Apr 20, 2002 at 14:44 UTC
That only sorts `@emails` by domains. Quite admittedly. But to quote the original poster: How do I alphabetize a list of email addresses by domain? ..but I can quite see your point. Anyways, you'll want to plonk an "or" between your two lines of code so that it compiles. :) Depending on how much the anonymous monk cares, they may or may not want to go whole hog and use Zaxo's more precise and tolerant answer. perl -pe '"I lo`+$^X$\"$]!$/"=~m%(.)%s;$_=$1;y^`+*^e v^#$&V"+@( NO CARRIER'	[reply] [d/l]
Re: How do I alphabetize a list of email addresses by domain? by Zaxo (Archbishop) on Apr 20, 2002 at 09:02 UTC
Without trying to optimize anything, here's an approach using Mail::Address: `# @emails exists already use Mail::Address; my @sorted_by_domain_then_user = map { $_-> format } sort { $a->host cmp $b->host or $a->user cmp $b->user } map {Mail::Address->parse($_)} @emails;` [download] This may not be exactly what you want, but should be close. After Compline, Zaxo	[reply] [d/l]
Re: How do I alphabetize a list of email addresses by domain? by particle (Vicar) on Apr 20, 2002 at 13:24 UTC
`my @emails = qw/bob@a.com adam@c.com bob@c.com ralph@b.a.com/; { local $,="\n"; print @emails, $n; print map { scalar reverse } sort( map { scalar reverse } @emails +), $/; }` [download] prints: `bob@a.com adam@c.com bob@c.com ralph@b.a.com ralph@b.a.com bob@a.com bob@c.com adam@c.com` [download] $, and $/ are merely for printing. you'd probably want something like `@sorted_emails = map { scalar reverse } sort( map { scalar reverse } @ +emails );` [download] ~Particle ;Þ	[reply] [d/l] [select]
Re: Re: How do I alphabetize a list of email addresses by domain? by japhy (Canon) on Apr 20, 2002 at 15:06 UTC
This will break down when you encounter domain names not ending in ".com". _____________________________________________________ Jeff`[japhy]`Pinyan: Perl, regex, and perl hacker, who'd like a (from-home) job `s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;`	[reply]
Re: How do I alphabetize a list of email addresses by domain? by Anonymous Monk on Apr 20, 2002 at 22:45 UTC
thank you all.. i did some testing.. and my first idea seems to be the fastest (though i haven't tried the newer posts yet). i've created dummy lists of 100,1000,...1,000,000 emails, and this seems to take half as much time as the first reply `$i = 0; for (@emails){ @email = split /@/, $_; push @{ $domains{$email[1]} }, $i; $prefixes[$i] = $email[0]; $i++; } foreach $key (sort keys %domains) { foreach ( @{ $domains{$key} } ) { push @sortedEmails, ( $prefixes[$_] . "@" . $key ); } }` [download]	[reply] [d/l]
Re: How do I alphabetize a list of email addresses by domain? by lemming (Priest) on Apr 21, 2002 at 01:35 UTC
Another thing to watch out for: username@machinename.domainname.ext	[reply]
Re: How do I alphabetize a list of email addresses by domain? by Anonymous Monk on Apr 21, 2002 at 19:37 UTC
well, i need to do this to feed a mailinglist into Mail::Bulkmail -- which can send emails within 1 envelope to each machine... so the machinename.domainname.tld works in this case anyways, i noticed a way to make it even slightly faster (about 8%)... `%domains = {}; for (@emails){ @email = split /@/, $_; if (!$domains{$email[1]}){ $domains{$email[1]} = []; } push @{ $domains{$email[1]} }, $email[0]; } foreach $domain (sort keys %domains) { foreach $recipient ( @{ $domains{$domain} } ) { push @sorted, ( $recipient . "@" . $domain ); } }` [download]	[reply] [d/l]