http://www.perlmonks.org?node_id=598285


in reply to Using map and grep to Sort one list using another list

Sure you can use map: 
my @final = 
    grep {@$_} 
    map {
        my $key = $_;
        [ grep{ m/^\d\|\d\|\d\|$key\|\d$/ } @records ]
    }
    @keys;

[download]

But I am missing the 'sort' bit of the title in your code...

--shmem 

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

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Re^2: Using map and grep to Sort one list using another list
by AntsPants (Novice) on Feb 05, 2007 at 13:37 UTC
    The sort is a mistake. Just keeping you on your toes. Now, no one's gonna believe this but ......... I'm sure while trying to solve this problem I wrote the following code 
    my @keys = ( qw|a e i o u| );
my @records = ();
push @records, '1|2|3|d|4';
push @records, '1|2|3|a|4';
push @records, '1|2|3|d|4';
push @records, '1|2|3|o|4';

my @final = ();
my @result = ();
@result = map { my $index = $_;
                grep{ m/^\d\|\d\|\d\|$keys[$index]\|\d$/ } @records
              } 0..$#keys;
print map{ "$result[$_]\n" } 0..$#result

    [download]
    which didn;t work. And while replying to your soln, I just re-ran that code and it worked!!!!!!! Hmmmmmmmmmm. Thank you all for replying anyway. I feel such a fool. -Ants
[reply]
[d/l]

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