On 11/22/2017 05:03 AM, Serhiy Storchaka wrote:

 From 
https://stackoverflow.com/questions/45190729/differences-between-generator-comprehension-expressions.

     g = [(yield i) for i in range(3)]

Syntactically this looks like a list comprehension, and g should be a list, 
right? But actually it is a generator. This
code is equivalent to the following code:

     def _make_list(it):
         result = []
         for i in it:
             result.append(yield i)
         return result
     g = _make_list(iter(range(3)))

Due to "yield" in the expression _make_list() is not a function returning a 
list, but a generator function returning a
generator.

The [] syntax says g should be list.  Seems to me we could do either of:

1)  raise if the returned object is not a list;
2)  wrap a returned object in a list if it isn't one already;

In other words, (2) would make

   g = [(yield i) for i in range(3)]

and

   g = [((yield i) for i in range(3))]

be the same.

I have no idea how either of those solutions would interact with async/await.

--
~Ethan~
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