Why chain grep() and map() if you can just use grep()?

my $dir = "/tmp";
opendir my $dh, $dir
    or die "opendir: $!";

my @files = grep { $_ = "$dir/$_"; -f && m/\.dat$/ } readdir($dh);

[download]

It works because grep() makes $_ an alias for a list element so it can be modified in-place. Some caution is advised however (see perlfunc entry for grep() for details).

PS This code may also be a bit more efficient as it doesn't create a copy of an array returned by readdir() while doing map() but I'm not 100% sure.

In reply to Re^2: Get fullpath of file using grep by jmacloue
in thread Get fullpath of file using grep by Anonymous Monk

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