Patrick R.Michaud (via RT) wrote:
Whenever a PAST::Op node gets a non-PAST child, PCT currently
throws a cryptic exception message like:
Method 'named' not found for invocant of class 'Perl6::Grammar'
A better exception message would be something like:
Perl6::Grammar ("2") child of PAST::Op cannot be converted to POST.
If you want a different exception message, you need to catch the type of
the child before calling the method on it. You can call 'VTABLE_isa' if
PAST nodes all share a parent, or you can call 'VTABLE_can' to check if
the object can perform the method.
Though, the cheapest option may be to simply wrap non-PAST children in a
PAST-compatible proxy. (That assumes that the non-PAST children are
intentionally there, and aren't slipping in by mistake.)
Allison
