Thanks a thousands for the work around!
I saw it working in the playground and I reported it in my project, but I still
got the same error. Then I reminded that I had [put doc comments in my
template](https://github.com/nim-lang/Nim/issues/9230). Bingo! That was the
reason again for this error.
And in order to keep the doc comments, the issue shows that strangely
template pairs*(m: Melon): tuple[key: int, val: int] = ##
## Works
(iterator(melon: Melon): tuple[key: int, val: int] =
...
Run
while
template pairs*(m: Melon): tuple[key: int, val: int] =
## Does not work! ==> Error: ignored invalid for loop
(iterator(melon: Melon): tuple[key: int, val: int] =
...
Run
doesn't!
Nim parser accepts a very flexible syntax that makes the language extensible
but is full of mystery.
