🚧 progress: Import existing sources and tests from js-itertools.

README.md

@@ -4,13 +4,17 @@
 Iterable consumption for JavaScript.
 See [docs](https://iterable-iterator.github.io/consume/index.html).
 
-> :building_construction: Caveat emptor! This is work in progress. Code may be
-> working. Documentation may be present. Coherence may be. Maybe.
-
 > :warning: Depending on your environment, the code may require
 > `regeneratorRuntime` to be defined, for instance by importing
 > [regenerator-runtime/runtime](https://www.npmjs.com/package/regenerator-runtime).
 
+```js
+import {exhaust} from '@iterable-iterator/consume';
+import {map} from '@iterable-iterator/map';
+import {range} from '@iterable-iterator/range';
+exhaust(map((i) => {console.log(i)}, range(10))); // 0 1 2 ...
+```
+
 [![License](https://img.shields.io/github/license/iterable-iterator/consume.svg)](https://raw.githubusercontent.com/iterable-iterator/consume/main/LICENSE)
 [![Version](https://img.shields.io/npm/v/@iterable-iterator/consume.svg)](https://www.npmjs.org/package/@iterable-iterator/consume)
 [![Tests](https://img.shields.io/github/workflow/status/iterable-iterator/consume/ci:test?event=push&label=tests)](https://github.com/iterable-iterator/consume/actions/workflows/ci:test.yml?query=branch:main)

package.json

@@ -65,6 +65,10 @@
     "@babel/preset-env": "7.14.0",
     "@babel/register": "7.13.16",
     "@commitlint/cli": "12.1.1",
+    "@iterable-iterator/iter": "^0.0.2",
+    "@iterable-iterator/list": "^0.0.2",
+    "@iterable-iterator/next": "^1.0.0",
+    "@iterable-iterator/range": "^0.0.1",
     "@js-library/commitlint-config": "0.0.4",
     "ava": "3.15.0",
     "babel-plugin-transform-remove-console": "6.9.4",

src/consume.js

@@ -0,0 +1,11 @@
+/**
+ * Consumes a given number of iterations of the input iterator.
+ *
+ * @param {Iterator} iterator - The input iterator.
+ * @param {Number} n - The number of iterations to consume.
+ *
+ */
+export default function consume(iterator, n) {
+	// eslint-disable-next-line no-empty
+	while (n-- > 0 && !iterator.next().done) {}
+}

src/exhaust.js

@@ -0,0 +1,15 @@
+/**
+ * Exhausts the input iterator.
+ *
+ * @example
+ * let it = range( 1000 ) ;
+ * exhaust( it ) ;
+ * list( it ) ; // returns []
+ *
+ * @param {Iterator} iterator - The input iterator.
+ *
+ */
+export default function exhaust(iterator) {
+	// eslint-disable-next-line no-empty,no-unused-vars,prettier/prettier
+	for (const item of iterator) {}
+}

src/index.js

@@ -1,2 +1,2 @@
-const answer = 42;
-export default answer;
+export {default as consume} from './consume.js';
+export {default as exhaust} from './exhaust.js';

test/src/consume.js

@@ -0,0 +1,15 @@
+import test from 'ava';
+
+import {range} from '@iterable-iterator/range';
+import {list} from '@iterable-iterator/list';
+import {consume} from '../../src/index.js';
+
+test('consume', (t) => {
+	const iterator = range(100);
+
+	consume(iterator, 37);
+
+	const output = list(iterator);
+
+	t.deepEqual(output, list(range(37, 100)));
+});

test/src/exhaust.js

@@ -0,0 +1,22 @@
+import test from 'ava';
+
+import {iter} from '@iterable-iterator/iter';
+import {next} from '@iterable-iterator/next';
+import {range} from '@iterable-iterator/range';
+import {list} from '@iterable-iterator/list';
+import {exhaust} from '../../src/index.js';
+
+test('exhaust', (t) => {
+	const iterator = iter(range(0, 100, 1));
+
+	const head = function* (iterator, n) {
+		// eslint-disable-next-line no-unused-vars
+		for (const _ of range(n)) yield next(iterator);
+	};
+
+	exhaust(head(iterator, 37));
+
+	const output = list(iterator);
+
+	t.deepEqual(output, list(range(37, 100, 1)));
+});