I'd like to know how in a module to tell if a function foo has been exported (when it isn't exported by default). That is,

 use ThisModule qw(foo);

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How in ThisModule can I tell that foo is being exported.

The real reason is that foo requires a bit of initialization, and I don't want to do this unless necessary.

I could do something like:

{
  my $value = undef;

  sub foo {
    unless (defined $value) {
      # initialize $value here
    }
    # do foo stuff using $value here
  }
}

[download]

I believe this isn't Apache mod_perl-friendly. (Or am I wrong?)

Suggestions to answer both problems (how to tell if a function is exported from within a module, and the best way to initialize a variable the first time a function is called) would be helpful.

In reply to How to tell if a sub has been exported? by rrwo

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