Sorry if this is a dumb question, why is this weird in Python? I use R as my main language and this is exactly how I would expect it to work. Does Python not do this naturally?
> count::{#x}
These two expressions are not valid in R or Python. They are implicitly declaring a function without declaring the arguments, it is implicitly iterating over the array and returning the result (all features of array languages to make it more concise).
Python’s + and / are a function of two objects (dyadic) and are syntactic sugar (they can’t be treated as function values, thats what the operator module is for): https://docs.python.org/3/reference/datamodel.html#object.__...
The array languages optimize for concise code so a lot of things are done implicitly that are done explicitly in Python.
The python equivalent:
> _sum = lambda x : functools.reduce(operator.add, x)
> _count = lambda x: functools.reduce(lambda acc, _: acc + 1, x, 0)
Of course in python and R there are built ins for these already (sum(x) and len(x)) but this is just to show what array languages are doing for you.
Notice how they're _defining_ the "sum" operation there. Instead of being something builtin, they defined "sum" as {+/x}.
{+/x} is the interesting part. That's Klong. It's not being able to define a "sum" operation, it's that "sum" can be expressed as {+/x}. That's very different than both R and python.