RFC: qualified vs unqualified names in defining instance methods

Malcolm Wallace malcolm.wallace at cs.york.ac.uk
Fri Apr 25 10:52:27 EDT 2008


> It is illegal to give a binding for a class method that is not in  
> scope, but the    name under which it is in scope is immaterial; in  
> particular, it may be a    qualified name.

I believe this was a change introduced in H'98 to tidy up the  
language.  Previously, if a class was imported qualified, it was only  
possible to declare an instance method by using a qualified name on  
the lhs.  It was felt that this was an oddity, because there are no  
other situations in which it was even possible to define a variable  
with an explicitly-qualified name, and in any case the qualification  
was entirely redundant, because there was no ambiguity.

Additionally, permitting a qualified name to appear in the  
definitional position of any declaration led to ambiguity in parsing.

Regards,
     Malcolm



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