Most likely the 'load it if we need it' failed for a second object because PDL was already loaded. I was thinking more in terms of "use it if it's available" in any case. The following code implements that:

use strict; use warnings; package TestPDL; my $PDLLoaded = eval { require 'PDL.pm'; PDL->import (); 1; }; sub new { my ($class, %params) = @_; $params{havePDL} = $PDLLoaded; return bless \%params, $class; } package main; my $obj = TestPDL->new (); my $obj2 = TestPDL->new (); print $obj2->{havePDL} ? "Have PDL available" : "PDL not present or object create failed";

I'd write one basic object that does common stuff then derive from that to specialise for additional capabilities. Following that thought, I'd arrange the name space as Sport::Analytics::SRS for the basic module then Sport::Analytics::SRS::Cricket for the Cricket specialisation.

This technique allows a PDL only implementation for tricky or computationally expensive stuff with a pure Perl implementation provided either in the module or in a derived class at some point in the future if there is a need for it.

True laziness is hard work

In reply to Re^3: From test harness to CPAN by GrandFather
in thread From test harness to CPAN by dwm042

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