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perlmodulerequire

How can I write code that optionally uses a module if it exists?

If I want to write code that optionally uses a module how can I do it? For example, if I want to write code that warns Dumping an object if Data::Dumper is available or otherwise just warns, how can I do that?

Solution

  • This is an effective idiom for loading an optional module,

    use constant has_Module => defined eval { require Module };

    This will require the module if available, and store the status in a constant.

    You can use this like,

    use constant has_DataDumper => defined eval { require Data::Dumper };

warn "got object";
if ( has_DataDumper ) {
  warn Data::Dumper::Dumper( $obj );
}