[query] Add enumerate, deprecate zip_with_index

[johnc1231]

zip_with_index seems based on Scala's zipWithIndex. Here I deprecate that in favor of using the more pythonic enumerate. To match the signature of the python function, I add a start argument and make our custom index_first argument keyword only.

[akotlar]

does this need to be int32?

[johnc1231]

Yes, because currently our arrays store their length as an int32, so that's what hl.range expects. All the ndarray stuff stores the shape as an int64 because I imagine we will eventually want to blow past 2^31 as an array length limit.

[akotlar]

one q

[akotlar]

I would say something like "the starting 'index'", index can be first or second.

[johnc1231]

So the reason I worded it the way I did was because I was afraid to give the implication that "index" meant "indexing into a (i.e., specifying start = 2 would mean to start at position 2 of a)".

[akotlar]

Let's make our language consistent with Python's enumerate method, or if you feel strongly that this isn't the right direction, make our language internally consistent. We use "index" throughout, and "label" does not indicate that the number included in the tuple is ordinal.

Here is how Python's enumerate is described elsewhere:

"The next() method of the iterator returned by enumerate() returns a tuple containing a count (from start which defaults to 0) and the values obtained from iterating over iterable."

• https://docs.python.org/3/library/functions.html#enumerate

"And there is more! enumerate also accepts an optional argument that allows us to specify the starting index of the counter."

• https://book.pythontips.com/en/latest/enumerate.html

"Start: the index value from which the counter is
to be started, by default it is 0 "

• https://www.geeksforgeeks.org/enumerate-in-python/

A few of our uses of "index":
"Returns an array of (index, element) tuples."
"Array of (index, element) or (element, index) tuples."
"The number the first element of the array is labeled with.
index_first: :obj:bool ... If True, the index is the first value of the element tuples"

[johnc1231]

You've convinced me. I'll go with language that includes "index", that seems to be the general understanding. I like "The index value from which the counter is started", I think that's clear.

Fixed

[akotlar]

I like counter, nice John!