12 Jun
2006
12 Jun
'06
5:29 p.m.
>> "SIGOURE" == SIGOURE Benoit
<sigoure.benoit(a)lrde.epita.fr> writes:
Fix boxing of meta-if at Expression level.
The new test fails because of an ambiguity. This ambiguity is a bit
tricky and (IMHO) must be resolved at the grammar level.
Basically we have:
test1 ? test1-true : test2 ? test2-true : test2-false
The ambiguity is:
(test1 ? test1-true : test2) ? test2-true : test2-false
-or-
test1 ? test1-true : (test2 ? test2-true : test2-false)
The second choice seems more natural and that's how it works in C.
Obviously we can't keep this ambiguity in the grammar.
You might want to read the third problem in this exam.