mypyc
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mypyc
Support yield and await nested in expressions
We currently don't support code like x = foo() + await bar(), since the result of calling foo() will be stored in a temporary that is not spilled to the environment.
I think that the best approach to solve this is to add another compiler pass that detects values that live across yields (which may just be the values that are live on function entry?) and spills them to the environment.
I think that scheme would also let us get rid of the manual spilling we do of compiler-induced temporaries in a bunch of situations (exception handling, with, etc). With some care it could maybe also subsume a bunch of the spill handling for nested functions too?
Would it be possible to confirm if the below is this same issue? It seems very similar, but it results in a runtime error as opposed to a compile-time -Werror=maybe-uninitialized error as in your example.
def gen():
a, b = 1, (yield 0)
print(a)
print(b)
yield 3
it = gen()
print(next(it))
print(it.send(2))
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "tupassign.py", line 9, in <module>
print(it.send(2))
File "tupassign.py", line -1, in gen
UnboundLocalError: local variable '' referenced before assignment
No rush or anything. Thanks!
