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    <p>Your friend is <a href="http://perldoc.perl.org/UNIVERSAL.html" rel="nofollow noreferrer"><code>can</code></a>. It returns a reference to the subroutine if it exists, null otherwise. It even does it correctly walking up the OO chain.</p> <pre><code>$self-&gt;{tests} = [ $self-&gt;can('_sub1'), $self-&gt;can('_sub2'), ]; # later for $tn (0..$#{$self-&gt;{tests}}) { ok defined $self-&gt;{tests}[$tn], "Function $tn is available."; } # and later my $ref = $self-&gt;{tests}[0]; $self-&gt;$ref(@args1); $ref = $self-&gt;{tests}[1]; $self-&gt;$ref(@args2); </code></pre> <p>Or, thanks to <a href="https://stackoverflow.com/questions/2804109/how-do-i-use-an-index-in-an-array-reference-as-a-method-reference-in-perl">this</a> question (which happens to be a variation of <a href="https://stackoverflow.com/questions/1836178/how-do-i-call-a-function-name-that-is-stored-in-a-hash-in-perl">this</a> question), you can call it directly:</p> <pre><code>$self-&gt;${\$self-&gt;{tests}[0]}(@args1); $self-&gt;${\$self-&gt;{tests}[1]}(@args1); </code></pre> <p>Note that the <code>\</code> gives us a reference to a the subref, which then gets dereferenced by the <code>${}</code> after <code>$self-&gt;</code>. Whew!</p> <p>To solve the timeliness issue brain d foy mentions, an alternative would be to simply make the {test} a subroutine itself, that returns a ref, and then you could get it at exactly the time you need it: </p> <pre><code>sub tests { return [ $self-&gt;can('_sub1'), $self-&gt;can('_sub2') ]; } </code></pre> <p>and then use it:</p> <pre><code>for $tn (0..$#{$self-&gt;tests()}) { ... } </code></pre> <p>Of course, if you have to iterate over the refs anyway, you might as well just go straight for passing the reference out:</p> <pre><code>for my $ref (0..$#{$self-&gt;tests()}) { $self-&gt;$ref(@args); } </code></pre>
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    1. POHow do I implement a dispatch table in a Perl OO module?
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    1. USRobert P
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    1. COI'd filter out the undefs earlier so you don't have to think about them at the higher level.
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      1. USbrian d foy
    2. COAgreed, if this was called in production code. My check there was if it was being used in a test suite (say, being built with [`Test::More`](http://search.cpan.org/perldoc?Test::More).)
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