rebol/r3 — pull request #105 by 0branch (2013-03-14 22:17:03+00:00)
Title: Prevent word duplication when appending to an object

(Addresses [Cure Code #1979](http://curecode.org/rebol3/ticket.rsp?id=1979).)

Ensure that duplicate words in `block!` arguments are flagged as temporary, favouring the final value.

The linear search isn't ideal, though it means that existing structures can be re-used without further allocation.