Functions defined inside if blocks don't do variable lookup correctly

[LeszekSwirski]

If I define an inner function inside an if block, it fails to look up values that it closes over, doing e.g. a global lookup instead:

value = 4
def make_func(value):
    if value == 0:
        def inner():
            log.info(f"value = {value}")
        return inner

make_func(0)()
---
value = 4

Interestingly, however, if there is an inner function defined outside the if block, the one inside the if block works as it should.

value = 4
def make_func(value):
    if value == 0:
        def inner():
            log.info(f"value = {value}")
        return inner
    
    def fix():
        pass

make_func(0)()
---
value = 0

[dlashua]

This is a side effect of the way function definitions work in pyscript. Under def inner you can try adding nonlocal value. I've had some luck with this.

[LeszekSwirski]

Nope:

value = 4
def make_func(value):
    if value == 0:
        def inner():
            nonlocal value
            log.info(f"value = {value}")
        return inner
    
make_func(0)()
---
value = 4

[dlashua]

I have tested this myself (and every variation I can think of). It is indeed broken. Hopefully @craigbarratt can fix it.

[craigbarratt]

Yikes. It doesn't correctly detect inner functions inside nested statements, which then means the correct variable scoping isn't applied. I pushed a fix f4f32f4.

A workaround for the existing code is to define a dummy inner function at the top-level, eg:

value = 4
def make_func(value):
    if 1:
        def real_inner():
            log.info(f"value = {value}")
        return real_inner
    def dummy_inner():
       pass

[ALERTua]

@LeszekSwirski Has your problem been fixed? Could you please update the ticket or close it? Thank you

[LeszekSwirski]

Honestly, I still just have the workaround in my own config, but from the looks of it it's fixed.