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Postings from December 2009
On 12/24/2009 05:34 PM, Chris Prather wrote:
> On Thu, Dec 24, 2009 at 4:55 PM, Mike Friedman<friedo@friedo.com> wrote:
>
>> You should be able to do this with triggers. For example:
>>
>> has foo => ( isa => 'Str', is => 'rw', trigger => \&_munge_foo );
>>
>> sub _munge_foo {
>> my ( $self, $new_foo, $old_foo ) = @_;
>>
>> $new_foo =~ s/\W+/_/gs;
>> $self->{foo} = $new_foo;
>> }
>>
>> The trigger will be called every time foo is set, including in the constructor.
>>
>>
>> Mike
>>
> A Trigger really is the wrong way to go about this. While yes this
> will work it's not considered "best practice".
>
> What you *do* want is a TypeConstraint and a Coercion.
>
> use Moose::Util::TypeConstraints;
>
> subtype MyAppCleanStr => as Str => where { $_ !~ /\W+/gs }; # make a
> TypeConstraint based on what you want
> coerce MyAppCleanStr => from Str => via { $_ =~ s/\W+/_/gs }; # define
> how to convert dirty Str to a Clean Str
>
> has foo => ( isa => 'MyAppCleanStr', is => 'rw', coerce => 1): # tell
> Moose you want to coerce for this attribute.
>
> -Chris
>
Great -- thanks, guys. I'll read up on both of those.
-Sir
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