PR# 16947 Once function anchored to feature in another class incorrectly called VFFD(7) error

Problem Report Summary

Submitter: prestoat2000

Category: Compiler

Priority: Medium

Date: 2010/07/06

Class: Bug

Severity: Non-critical

Number: 16947

Release: 6.6.83767

Confidential: No

Status: Closed

Responsible:

Environment: Mozilla/5.0 (X11; U; SunOS sun4u; en-US; rv:1.9.0.10) Gecko/2009042715 Firefox/3.0.10 Solaris 10 on SPARC

Synopsis: Once function anchored to feature in another class incorrectly called VFFD(7) error

Description

A class (generic or not) with a once function whose type is
a qualified anchored type that does not involve any formal generics,
`like Current' or any anchors to features of the class (i.e., it
involves only anchors to "remote" features in other classes)
is reported to violate VFFD(7).

This test case does not violate the letter of VFFD in ECMA-367 but it does
seem to violate the spirit.  The type won't change in descendant
classes and also won't change with different actual generic
parameters, so it seems to me that it should be considered a
stand-alone type.

If I'm wrong or if you don't intend to allow this case, please 
correct the test and close this report.

Added eweasel test anchor050 for this (potential) bug.

To Reproduce

Run eweasel test anchor050.

Problem Report Interactions

From:alexk_es Date:2010/08/12 Status: Closed Download

Fixed in rev#84155 of EiffelStudio 6.7 intermediate release.

From:prestoat2000 Date:2010/07/29 Download

There are other places where anchored types are currently not allowed,
where they should perhaps be allowed if the type cannot change in
descendant classes.  For example, the following seem to me like they
ought to be allowed:

   inherit
         MY_GENERIC_CLASS [like {TEST}.x]
   convert
         from_type ({like {TEST}.x})