This has been brought up multiple times. Last time was on this thread https://mail.python.org/pipermail/python-ideas/2016-October/043024.html.

On Tue, Nov 21, 2017 at 3:13 AM, bunslow <bunslow@gmail.com> wrote:

Nothing so bombastic this time. The heapq functions are basically all named "heapsomething", and basically all take a "heap" for their first argument, with supplementary args coming after. It's a textbook example of the (hypothetical) Object Oriented Manifesto™ where defining a class increases type safety and programmers' conceptual clarity. There're practically no drawbacks, and the code to be added would be very simple. Updating the tests and docs would probably be harder.

In pure Python, such a class would look like this:

class Heap(list):

    def __init__(self, iterable=None):

        if iterable:

            super().__init__(iterable)

        else:

            super().__init__()

        self.heapify()

    push = heapq.heappush

    pop = heapq.heappop

    pushpop = heapq.heappushpop

    replace = heapq.heapreplace

    heapify = heapq.heapify

    # This could be a simple wrapper as well, but I had the following thoughts anyways, so here they are

    def nsmallest(self, n, key=None):

        # heapq.nsmallest makes a *max* heap of the first n elements,

        # while we know that self is already a min heap, so we can

        # make the max heap construction faster

        self[:n] = reversed(self[:n])

        return heapq.nsmallest(n, self, key)

    # do we define nlargest on a minheap??


Wrapping around the C builtin functions (which aren't descriptors) would be a bit harder, but not much so:

from functools import partial

class Heap(list):

    def __init__(self, iterable=None):

        if iterable:

            super().__init__(iterable)

        else:

            super().__init__()

        self.heapify = partial(heapq.heapify, self)

        self.push = partial(heapq.heappush, self)

        ...

        self.heapify()

Thoughts?

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Sebastian Kreft