say @links looks like this: 
@links =
(
    [1,2,3],
    [4,5,6],
    [7,8,9]
);

[download]
and you apply 
my @urls = map { $_->[0] } @links;

[download]
@urls will end up as 
@urls = (1,4,7);

[download]

basically the code will produce a list that consists of the first elements of the anonymous arrays in @links.
see perlref

holli, regexed monk

In reply to Re: map confusion by holli
in thread map confusion by knewter

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