Well, your use statements will get executed at compile-time whether the condition is true or not. To conditionally load a module at runtime, you can do this: 
if ( $want_to_check_email ) { 
    unshift @INC, $mod_path;
    require Email::Valid;
    Email::Valid->import;
}

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In reply to Re^2: use lib problem. by friedo
in thread use lib problem. by tanger

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