push foreach glob

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

I'm trying to separate a list of MP3 files into two groups: the ones matching /ad/ and the rest.

I am puzzled why this works:

perl -le 'push @{$f[/ad/]}, $_ foreach glob("*.mp3"); use Data::Dumper
+; print Dumper(\@f)'
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while this does not:

perl -le '@f = glob("*.mp3"); push @{$f[/ad/]}, $_ foreach @f; use Dat
+a::Dumper; print Dumper(\@f)'
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The latter puts everything into $f[0], matching or not.

This is perl, v5.10.0 built for i386-linux-thread-multi
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