Different results.

According to what you said, the following should print "0" instead of "1":

my $x; BEGIN { $x = 0 }
my $f = sub { $x };
++$x;
print $f->();
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Let's say you didn't mean the above. According to what you said, the following should print "11" instead of "12":

for (1..2) {
    my $x = $_;
    print sub { $x }->();
}
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As JadeNB put it:

* I'm intentionally being a bit sloppy here: as ikegami mentions, closures close over variables, not values; but, as the warning that you quote mentions, the actual variable that is closed over will no longer be accessible at the end of the subroutine invocation, so that there is no further way to change its value.

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