Hello monks,

I've noticed that when I use Types that I make with Type::Library, to validate named incoming arguments, with Type::Params, using a slurpy Dict, per the docs, I lose the custom error message set in the library.

# in package MyModule::Types
declare DBPrefix, as Optional[StrMatch[ qr/ \w+_ /x ]],
  message { 'The table prefix must end in an underscore. ' };

# in package MyModule
use Type::Params qw/ compile /;
use My::Types qw/ DBPrefix /; 

state $validate = compile( DBPrefix );
my ($param) = $validate->( @_ );

# in foo.pl
$obj->method( 'bar' );

# output:
# The table prefix must end in an underscore.  (in $_[0]) at ./foo.pl 
+line 11
#    "DBPrefix" is a subtype of "Optional[StrMatch[(?^x: \w+_ )]]"
#    Value "bar" did not pass type constraint "Optional[StrMatch[(?^x:
+ \w+_ )]]" (in $_[0])
#    $_[0] exists
#    "Optional[StrMatch[(?^x: \w+_ )]]" constrains $_[0] with "StrMatc
+h[(?^x: \w+_ )]" if it exists
#    Value "bar" did not pass type constraint "StrMatch[(?^x: \w+_ )]"
+ (in $_[0])
#    "StrMatch[(?^x: \w+_ )]" is defined as: do { !ref($_) and $_ =~ $
+Types::Standard::_StrMatch{"(?^x: \\w+_ )"} }
[download]

That's a little more than I really need, but it gives me my custom message at the beginning.

Now, when I want to go to named arguments, I follow the manual:

state $validate = compile(slurpy Dict[ prefix => DBPrefix ]); #per the
+ docs for named args
my ($param) = $validate->( @_ );

# in foo.pl
$obj->method( 'bar' );

# output :
# Reference {"prefix" => "bar"} did not pass type constraint "Dict[pre
+fix=>DBPrefix]" (in $SLURPY) at ./foo.pl line 11
[download]

I need to use named args because some of them are completely optional. But I want to be able to return an error that tells the user how to fix the error!

Has anyone figured a way around this? Thanks ...