OO and procedural Interface

[David Cumming]

Hello

 

I want to update an existing module to support an OO and procedural interface. The module will be primarily OO, however it should still support for two main functions as a simple procedural interface.

 

I looked at CGI.pm and the way they do it is like this:

 

The well known param mothod which can all be called as a procedural function or OO function.

 

sub param {
    my($self,@p) = self_or_default(@_);
    return $self->all_parameters unless @p;
    my($name,$value,@other);

   etc.

}

 

A method to return $self or a default object to use within the calling method

 

sub self_or_default {
    return @_ if defined($_[0]) && (!ref($_[0])) &&($_[0] eq 'CGI');
    unless (defined($_[0]) &&
    (ref($_[0]) eq 'CGI' || UNIVERSAL::isa($_[0],'CGI')) # slightly optimized for common case
    ) {
$Q = $CGI::DefaultClass->new unless defined($Q);
unshift(@_,$Q);
    }
    return wantarray ? @_ : $Q;
}

 

I don't really follow the  $Q = $CGI::DefaultClass->new unless defined($Q); or DefaultClass logic used in above.

 

Is there a standard approach to making a module support both 00 and procedural interfaces? Any ideas? I just want to create $self if there isn't one. $self should inherit all the default properties made by new.

 

Dave

 

 

David Cumming

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