TIMTOWTDI, and I wanted to play with (?(condition)true-pattern|false-pattern) asserts.
Looks like this:

my $re =qr/
^(\d{1,3})$                             # Up to 3 digits
(?(?{ ($1<256 and $1>=0) })     # If in the correct range
                .?                      # An allways match
        |                       # Else
                .                       # Never going to match after e
+nd of string
)
/x;

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In reply to Re: Regexp for range of numbers by deibyz
in thread Regexp for range of numbers by loris

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