The question can easily be misunderstood, but my best guess is you want the user to choose what is executed. This means it is a method they name, not a module which has any number of methods including none. It is advisable to "use strict" in perl programs, so to translate data into a perl identifier, you need a dispatcher, e.g.:

use Try::Tiny;
while (my @parsed = &parseInput) {
    &dispatch(@parsed);
}

sub parseInput {
    my $inp = <>;
    chomp $inp;
    my @parsed = split $inp;
    return () if $parsed[0] eq `q`;
    return @parsed;
}

sub dispatch {
    my $cmd = shift;
    try { eval( '&' . $cmd . '(' . join ',', @_ . ');' ); }
    catch { print STDERR "Unrecognised command $cmd\n"; }
    # the above is a non-GUI example which would need adaptation      
+                                                        
}

# and add a sub xxx for each command xxx
[download]

---

---

• Are you posting in the right place? Check out Where do I post X? to know for sure.
• Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:

  <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>

• Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
• Want more info? How to link or How to display code and escape characters are good places to start.