petdance/scratch — Issue #795: add vtables for: get_pmc_keyed{_int,_str,}_lvalue ; and similarly for slice
Author: petdance
Created: 2011-11-14 06:13:33+00:00
State: open
Labels: core, Pri-normal, Sev-medium, todo

See discussion starting at:
http://irclog.perlgeek.de/parrot/2009-06-23#i_1260446

In short, HLLs expect to be able to bind to an element (or slice) of a collection as an lvalue, even if that collection is implemented as a packed array of non-PMCs underneath the covers. Indexing into a collection for rvalue return and for lvalue return are different operations; thus we need lvalue variants of get_pmc_keyed* to go along with the current rvalue variants, and the HLLs need to use the correct variant for the operation they wish to perform.

Originally http://trac.parrot.org/parrot/ticket/787 by @japhb