Shouldn't that be 

m/
  \A
  (?:
    [[:alpha:][:digit:]]
    [[:alpha:][:digit:]-]*
  )?
  \z
/x

[download]

Your version requires that at least one character be present.

In reply to Re^2: Regular Expression - Need HElp..pls by ikegami
in thread Regular Expression - Need HElp..pls by dani_cv_perl

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