Ever find yourself wrangling in a map when you're trying to change each element of a list to a new value via s/// or tr/// only to recall that substitution or transliteration returns a count, not the changed string? So you end up doing something ugly like: 
@new = map { my $x = $_; $x =~ s/foo/bar/g; $x } @old;

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That's just because you're doing it inside out. Much simpler to use a foreach loop, as shown in this snippet.
s/foo/bar/g for (@new = @old);
- or -
tr/A-Z/N-ZA-M/ for (@new = @old);

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In reply to make a new list by substituting an old list by merlyn

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