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From: Ian Kelly <ian.g.kelly@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: Cannot step through asynchronous iterator manually
Date: Sat, 30 Jan 2016 09:42:54 -0700
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On Jan 30, 2016 7:13 AM, "Oscar Benjamin" <oscar.j.benjamin@gmail.com>
wrote:
>
> I haven't used PEP 492 yet but what about:
>
> async def aslice(asynciterator, end):
>     if end == 0:
>         return []
>    items = []
>    async for item in asynciterator:
>        items.append(item)
>        if len(items) == end:
>            break
>     return items
>
> rows = await aslice(cur, 2)
>
> AFAICT there's no generator-function-style syntax for writing an async
> iterator so you'd have to make a class with the appropriate methods if
> you wanted to be able to loop over aslice with async for.

Before you go any further with this, be sure to check out the aitertools
third-party module. I haven't done anything with it myself, but it already
claims to provide aiter and anext as well as async versions of everything
in the standard itertools module.