Type errors using (x, _, _) = (1, 2, "3")

[timabbott]

It's a common pattern to use assignment to _ in code to ignore variables that aren't used, and mypy doesn't support that:

/home/tabbott/foo.py:2: error: Incompatible types in assignment (expression has type "str", variable has type "int")

In my real code the usage looks more like this:

for (email, _, _, _) in users:                                                                                                                                     
    ...

Not sure whether the right answer is to change the code, but I think I'd flag this as an interesting case that may be somewhat common.

[gvanrossum]

It's common enough to flag a few variable names as special as targets: _, __, and unused have all been recommended at various times.

[JelleZijlstra]

This is a duplicate of #465.

[ilevkivskyi]

Yes, it looks like this is a duplicate. I think it makes sense to only keep one of them open.