petdance/scratch — Issue #71: deprecate PMC multiple inheritance
Author: petdance
Created: 2011-11-01 05:41:08+00:00
State: open
Labels: pmc2c, Pri-normal, rfc, Sev-medium

I'd like to deprecate the behavior of pmc2c which allows C-level PMC multiple inheritance. The behavior needs supporting code which isn't properly tested in Parrot's test suite. Any modification to pmc2c that deals with a PMC's parents also needs to take this behavior into account or risk causing failures in HLLs which may not be reported for some time.
Currently the only language I know of that uses MI is Lua (partcl no longer needs it), and coke claims that MI doesn't allow anything that can't be done in another way. I've asked fperrad about how much work it would be for him to avoid MI. If it's a big deal for him (or any other HLL devs) I don't mind continuing to support it.

Once I hear back from fperrad and don't get any other objections, I'll add a proper deprecation notice so this feature can be removed post-1.4.

Originally http://trac.parrot.org/parrot/ticket/774