Validating against a Moose type-constraint without setting field

locked_user sundialsvc4 has asked for the wisdom of the Perl Monks concerning the following question:

(Pardon me ... I am having a Senior Moment™ ...)

I need to validate a value against the type-constraint associated with a particular Moose has field, without actually setting the field’s value. That is to say, given the field name and a variable containing a value that I want to check, I want to fire the field’s validation-constraint if it has one, and see if the value that I am presenting is agreeable to it. (I had written notes that Moose’s “Recipe #4” told how to do that, but I can’t find that example now. So, heck, thought I’d just ask...)

Thanks in advance. (Now, where in the heck did I put my glasses? Durn things are, uhh, “obviously broken” anyway ...)

Replies are listed 'Best First'.
Re: Validating against a Moose type-constraint without setting field by Anonymous Monk on Nov 15, 2011 at 15:37 UTC
Moose’s “Recipe #4” Moose::Cookbook::Meta::Recipe4	[reply]
Re: Validating against a Moose type-constraint without setting field by stvn (Monsignor) on Nov 23, 2011 at 19:23 UTC
You want this: `use Moose::Util::TypeConstraints qw[ find_type_constraint ]; # ... find_type_constraint('MyType')->check( $my_value );` [download] Basically all this does it locate the underlying type constraint object for you. Alternately you could find the type constraint object in the actual class, which is explain in Moose::Cookbook::Snack::Types. -stvn	[reply] [d/l]
Re: Validating against a Moose type-constraint without setting field by locked_user sundialsvc4 (Abbot) on Nov 15, 2011 at 16:49 UTC
Are you sure about that? “Meta” doesn’t seem to be it. My notes said that (I think) Moose::Cookbook::Basics::Recipe4 contained the magic spell, but durned if (squint, peer, wince...) I can see it now.