[Python-ideas] Sequence views

[Serhiy Storchaka]

On 18.07.16 01:21, Wes Turner wrote:
> There are a number of generic implementations of these sequence algorithms:
>
> * http://toolz.readthedocs.io/en/latest/api.html#itertoolz
> * https://github.com/kachayev/fn.py#itertools-recipes
> * http://funcy.readthedocs.io/en/stable/seqs.html
>    * http://docs.python.org/2/reference/expressions.html#slicings
>    * https://docs.python.org/2/library/itertools.html#itertools.islice
>    * https://docs.python.org/3/library/itertools.html#itertools.islice

Aren't all these implementations works with iterables and iterators?

> On Jul 17, 2016 3:23 PM, "Serhiy Storchaka"
> <storchaka at gmail.com
> <mailto:storchaka at gmail.com>> wrote:
>  >
>  > Maybe it's time to add a new module for sequence-specific functions
> (seqtools?). It should contain at least two classes or fabric functions:
>  >
>  > 1. A view that represents a sliced subsequence. Lazy equivalent of
> seq[start:end:step]. This feature is implemented in third-party module
> dataview [1].
>
> islice?

The result of itertools.islice() is not a sequence.

>  > 2. A view that represents a linear sequence as 2D array. Iterating
> this view emits non-intersecting chunks of the sequence. For example it
> can be used for representing the bytes object as a sequence of 1-byte
> bytes objects (as in 2.x), a generalized alternative to iterbytes() from
> PEP 467 [2].
>
> partition?
>
> http://toolz.readthedocs.io/en/latest/api.html#toolz.itertoolz.partition
> _all

toolz.itertoolz.partition() is just a generator.