Dear monks,

I am trying to understand how to use Exception::Class in a large-ish multimodule application. As part of the set of modules I made one package where I am planning to define all exceptions, i.e.: 
package Bio::Phylo::Exceptions;
use Exception::Class (
    'Bio::Phylo::Exceptions',
    'Bio::Phylo::Exceptions::BadNumber' =>
    { isa => 'Bio::Phylo::Exceptions' },
    'Bio::Phylo::Exceptions::BadString' =>
    { isa => 'Bio::Phylo::Exceptions' },
    'Bio::Phylo::Exceptions::BadFormat' =>
    { isa => 'Bio::Phylo::Exceptions' },
    'Bio::Phylo::Exceptions::ObjectMismatch' =>
    { isa => 'Bio::Phylo::Exceptions' }
);
1;

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So then, elsewhere in the modules, there might be OO getters and setters like this: 
use Scalar::Util qw(looks_like_number);

sub set_number {
   my ( $self, $number ) = @_;
   looks_like_number $number 
   ? $self->{'NUMBER'} = $number 
   : Bio::Phylo::Exceptions::BadNumber->throw(error => 'bad number');
}

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And then the user has to go through a contortion like: 
# try
eval { $obj->set_number(sdf7897) };

# catch
if (UNIVERSAL::isa($@,'Bio::Phylo::Exceptions::BadNumber')){
   # do something
}

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Is that how it works? Or are the exceptions caught inside the object methods?

Pardon my ignorance, but I've never worried about this before, and I wish to learn.

Thank you!

In reply to Exception::Class - how to use? by rvosa

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