functools

Module nustd.functools.

Nu surface for Python's functools.

Only reduce is modeled: it is the one functools member that is a runtime value operation (a fold over a stream). The rest are out of Nu's value model and intentionally absent:

• partial / partialmethod / cmp_to_key produce callables - Nu has no first-class function value at the user surface.
• lru_cache / cache / cached_property are stateful (memoization) - they need the effect model (not yet built).
• wraps / update_wrapper / total_ordering are decorators over Python metadata, not runtime operations.

Import like the stdlib:

from nustd.functools import reduce

Call

reduce

Fold iterable left-to-right with function (functools.reduce).

functools.reduce(function, iterable, initializer=<UNSET>)

Path nustd.functools.reduce. Defined on nustd.functools.functions, bound as a function. Builds Any.

function is a Nu query that reads the accumulator and the current item via a typed AttrRef - IntAttrRef("acc") and IntAttrRef("item") - so a sum is reduce(IntAttrRef("acc") + IntAttrRef("item"), xs). With initializer the accumulator starts there; otherwise at the first item.

Arguments

Undocumented: example.