heap

library0.2.7jsnpmunverified

A binary heap (priority queue) implementation in CoffeeScript/JavaScript, ported from Python's heapq module. Current stable version is 0.2.7 (last released in 2013). No release cadence; maintenance-only mode. Key differentiator: simple API with both instance methods (push, pop, peek) and static methods for arrays, plus nlargest/nsmallest utilities. Alternatives like `flatqueue` or `tinyqueue` may offer better performance or modern features.

testing

npm install heap

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · HEAP

heap

testingjavascriptv0.2.7

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

Heap

✓ var Heap = require('heap');

✗ import Heap from 'heap';

This package is CommonJS, not ESM. Use require(). For TypeScript, you may need to use `const Heap = require('heap') as any;` if no types are available.

Heap constructor

✓ var heap = new Heap();

✗ var heap = Heap();

Must use `new` keyword to instantiate. Without `new`, the constructor will not return a Heap instance.

Heap.push

✓ heap.push(item);

✗ Heap.push(item);

push() is an instance method, not static. Static methods operate on arrays directly (e.g., Heap.push(array, item)).

Creates a min-heap using custom compare function, pushes elements, pops the smallest, and uses static nlargest to find top 3 from an array.

var Heap = require('heap'); var heap = new Heap(function(a, b) { return a - b; }); heap.push(3); heap.push(1); heap.push(2); var smallest = heap.pop(); console.log(smallest); // 1 var array = [1, 3, 4, 2, 5]; var largest3 = Heap.nlargest(array, 3); console.log(largest3); // [5, 4, 3]

Debug

Known issues

gotchaHeap.pop() on an empty heap returns undefined.

fix

Check heap.empty() before calling heap.pop() or handle undefined gracefully.

affects: >=0.0.0

gotchaStatic methods modify the array in place, not returning a new array.

fix

Be aware that heapify(array) changes the array directly. Clone first if needed.

affects: >=0.0.0

deprecatedPackage is not actively maintained; last release in 2013.

fix

Consider using an alternative like tinyqueue or flatqueue which are more modern and maintained.

affects: >=0.0.0

gotchaThe comparison function for custom heaps must return negative/positive/zero, not boolean like other JavaScript sort comparators.

fix

Use `function cmp(a, b) { return a - b; }` for min-heap, not `function cmp(a, b) { return a < b; }`.

affects: >=0.0.0

Errors

Common errors & fixes

TypeError: heap.push is not a function

Calling push() statically on the Heap class instead of on an instance.

fix

Create an instance first: var heap = new Heap(); then use heap.push(item);

ReferenceError: require is not defined

Using require() in an ESM environment or browser without bundling.

fix

In browser, use a script tag to include the heap.js file. In Node ESM, use createRequire or switch to an alternative package.

Heap.nlargest is not a function

Using an outdated version or incorrect import (e.g., default import vs named import).

fix

Ensure you are using require('heap') which returns the Heap class, and check package version supports nlargest/nsmallest (available since 0.2.0).

Upgrade

Version history

0.2.7latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

8 hits · last 30 days

node

Resources

githubgit://github.com/qiao/heap.js ↗

packageheap ↗

homepagehttps://github.com/qiao/heap.js ↗