I've been trying to understand why these give different results: 
#!/usr/bin/perl
*alias0 = *_;
*alias1 = \$_;

@F = qw(A B C D);
s//Sample/;
$x = '%';

do {
    local $_ = 999;
    print "do: ( $_ $alias0 $alias1 )\n";
};

foreach (@F) {
    print $_;
    *_ = *x;
    print " : ( $_ $alias0 $alias1 )\n";
}

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My understanding was that foreach() implicitly did local $_; before starting the loop. But look at the output I get (from perl-5.8.0): 
do: ( 999 999 Sample )
A : ( % A Sample )
% : ( % B Sample )
% : ( % C Sample )
% : ( % D Sample )

[download]
What's going on here? How does $alias0 manage to get a reference to the loop variable inside the foreach?

In reply to Understanding typeglobs and local() by whio

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