{"id":20770357,"url":"https://github.com/stdlib-js/array-to-view-iterator-right","last_synced_at":"2025-04-30T13:42:36.119Z","repository":{"id":41373074,"uuid":"377219622","full_name":"stdlib-js/array-to-view-iterator-right","owner":"stdlib-js","description":"Create an iterator from an array-like object view, iterating from right to left.","archived":false,"fork":false,"pushed_at":"2025-03-24T01:33:44.000Z","size":1540,"stargazers_count":2,"open_issues_count":0,"forks_count":0,"subscribers_count":3,"default_branch":"main","last_synced_at":"2025-04-13T07:31:16.078Z","etag":null,"topics":["arr","array","iterate","iteration","iterator","javascript","node","node-js","nodejs","reverse","slice","stdlib","typed","typed-array","util","utilities","utility","utils","view"],"latest_commit_sha":null,"homepage":"https://github.com/stdlib-js/stdlib","language":"JavaScript","has_issues":false,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"apache-2.0","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/stdlib-js.png","metadata":{"files":{"readme":"README.md","changelog":"CHANGELOG.md","contributing":"CONTRIBUTING.md","funding":null,"license":"LICENSE","code_of_conduct":"CODE_OF_CONDUCT.md","threat_model":null,"audit":null,"citation":"CITATION.cff","codeowners":null,"security":"SECURITY.md","support":null,"governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null,"zenodo":null},"funding":{"github":["stdlib-js"],"open_collective":"stdlib","tidelift":"npm/@stdlib/stdlib"}},"created_at":"2021-06-15T16:00:10.000Z","updated_at":"2025-03-24T01:02:32.000Z","dependencies_parsed_at":"2024-01-01T06:33:56.786Z","dependency_job_id":"d79eb2e0-857f-4e6f-b4c6-e16bcd747c2b","html_url":"https://github.com/stdlib-js/array-to-view-iterator-right","commit_stats":{"total_commits":48,"total_committers":1,"mean_commits":48.0,"dds":0.0,"last_synced_commit":"20801c542922fa8158c0bb170531f942d2a27359"},"previous_names":[],"tags_count":22,"template":false,"template_full_name":null,"repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/stdlib-js%2Farray-to-view-iterator-right","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/stdlib-js%2Farray-to-view-iterator-right/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/stdlib-js%2Farray-to-view-iterator-right/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/stdlib-js%2Farray-to-view-iterator-right/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/stdlib-js","download_url":"https://codeload.github.com/stdlib-js/array-to-view-iterator-right/tar.gz/refs/heads/main","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":251494050,"owners_count":21598225,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2022-07-04T15:15:14.044Z","host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["arr","array","iterate","iteration","iterator","javascript","node","node-js","nodejs","reverse","slice","stdlib","typed","typed-array","util","utilities","utility","utils","view"],"created_at":"2024-11-17T12:08:54.822Z","updated_at":"2025-04-30T13:42:36.113Z","avatar_url":"https://github.com/stdlib-js.png","language":"JavaScript","readme":"\u003c!--\n\n@license Apache-2.0\n\nCopyright (c) 2019 The Stdlib Authors.\n\nLicensed under the Apache License, Version 2.0 (the \"License\");\nyou may not use this file except in compliance with the License.\nYou may obtain a copy of the License at\n\n   http://www.apache.org/licenses/LICENSE-2.0\n\nUnless required by applicable law or agreed to in writing, software\ndistributed under the License is distributed on an \"AS IS\" BASIS,\nWITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\nSee the License for the specific language governing permissions and\nlimitations under the License.\n\n--\u003e\n\n\n\u003cdetails\u003e\n  \u003csummary\u003e\n    About stdlib...\n  \u003c/summary\u003e\n  \u003cp\u003eWe believe in a future in which the web is a preferred environment for numerical computation. To help realize this future, we've built stdlib. stdlib is a standard library, with an emphasis on numerical and scientific computation, written in JavaScript (and C) for execution in browsers and in Node.js.\u003c/p\u003e\n  \u003cp\u003eThe library is fully decomposable, being architected in such a way that you can swap out and mix and match APIs and functionality to cater to your exact preferences and use cases.\u003c/p\u003e\n  \u003cp\u003eWhen you use stdlib, you can be absolutely certain that you are using the most thorough, rigorous, well-written, studied, documented, tested, measured, and high-quality code out there.\u003c/p\u003e\n  \u003cp\u003eTo join us in bringing numerical computing to the web, get started by checking us out on \u003ca href=\"https://github.com/stdlib-js/stdlib\"\u003eGitHub\u003c/a\u003e, and please consider \u003ca href=\"https://opencollective.com/stdlib\"\u003efinancially supporting stdlib\u003c/a\u003e. We greatly appreciate your continued support!\u003c/p\u003e\n\u003c/details\u003e\n\n# arrayview2iteratorRight\n\n[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] \u003c!-- [![dependencies][dependencies-image]][dependencies-url] --\u003e\n\n\u003e Create an iterator from an array-like object view, iterating from right to left.\n\n\u003c!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. --\u003e\n\n\u003csection class=\"intro\"\u003e\n\n\u003c/section\u003e\n\n\u003c!-- /.intro --\u003e\n\n\u003c!-- Package usage documentation. --\u003e\n\n\u003csection class=\"installation\"\u003e\n\n## Installation\n\n```bash\nnpm install @stdlib/array-to-view-iterator-right\n```\n\nAlternatively,\n\n-   To load the package in a website via a `script` tag without installation and bundlers, use the [ES Module][es-module] available on the [`esm`][esm-url] branch (see [README][esm-readme]).\n-   If you are using Deno, visit the [`deno`][deno-url] branch (see [README][deno-readme] for usage intructions).\n-   For use in Observable, or in browser/node environments, use the [Universal Module Definition (UMD)][umd] build available on the [`umd`][umd-url] branch (see [README][umd-readme]).\n\nThe [branches.md][branches-url] file summarizes the available branches and displays a diagram illustrating their relationships.\n\nTo view installation and usage instructions specific to each branch build, be sure to explicitly navigate to the respective README files on each branch, as linked to above.\n\n\u003c/section\u003e\n\n\u003csection class=\"usage\"\u003e\n\n## Usage\n\n```javascript\nvar arrayview2iteratorRight = require( '@stdlib/array-to-view-iterator-right' );\n```\n\n#### arrayview2iteratorRight( src\\[, begin\\[, end]]\\[, mapFcn\\[, thisArg]] )\n\nReturns an iterator which iterates from right to left over each element in an array-like `object` view.\n\n```javascript\nvar it = arrayview2iteratorRight( [ 1, 2, 3, 4 ] );\n// returns \u003cObject\u003e\n\nvar v = it.next().value;\n// returns 4\n\nv = it.next().value;\n// returns 3\n\nv = it.next().value;\n// returns 2\n\n// ...\n```\n\nThe returned iterator protocol-compliant object has the following properties:\n\n-   **next**: function which returns an iterator protocol-compliant object containing the next iterated value (if one exists) assigned to a `value` property and a `done` property having a `boolean` value indicating whether the iterator is finished.\n-   **return**: function which closes an iterator and returns a single (optional) argument in an iterator protocol-compliant object.\n\nThe `begin` and `end` arguments define the starting (inclusive) and ending (non-inclusive) indices of the array view. By default, the returned iterator starts iterating from the last element in an array-like `object` (i.e., from the \"end\"). To specify an alternative view end, provide an `end` argument (non-inclusive).\n\n```javascript\nvar it = arrayview2iteratorRight( [ 1, 2, 3, 4 ], 0, 3 );\n// returns \u003cObject\u003e\n\nvar v = it.next().value;\n// returns 3\n\nv = it.next().value;\n// returns 2\n\nv = it.next().value;\n// returns 1\n\nvar bool = it.next().done;\n// returns true\n```\n\nIf `end` is less than `0`, the first iterated value is resolved relative to the last view element. For example, the following generates the same behavior as in the previous example\n\n```javascript\nvar it = arrayview2iteratorRight( [ 1, 2, 3, 4 ], 0, -1 );\n// returns \u003cObject\u003e\n\nvar v = it.next().value;\n// returns 3\n\nv = it.next().value;\n// returns 2\n\nv = it.next().value;\n// returns 1\n\nvar bool = it.next().done;\n// returns true\n```\n\nBy default, the returned iterator iterates through the first element in an array-like `object` view. To specify an alternative view beginning, provide a `begin` argument (inclusive).\n\n```javascript\nvar it = arrayview2iteratorRight( [ 1, 2, 3, 4 ], 1 );\n// returns \u003cObject\u003e\n\nvar v = it.next().value;\n// returns 4\n\nv = it.next().value;\n// returns 3\n\nv = it.next().value;\n// returns 2\n\nvar bool = it.next().done;\n// returns true\n```\n\nIf `begin` is less than `0`, the last iterated value is resolved relative to the last view element. For example, the following generates the same behavior as in the previous example\n\n```javascript\nvar it = arrayview2iteratorRight( [ 1, 2, 3, 4 ], -3 );\n// returns \u003cObject\u003e\n\nvar v = it.next().value;\n// returns 4\n\nv = it.next().value;\n// returns 3\n\nv = it.next().value;\n// returns 2\n\nvar bool = it.next().done;\n// returns true\n```\n\nTo invoke a function for each `src` value, provide a callback function.\n\n```javascript\nfunction fcn( v ) {\n    return v * 10.0;\n}\n\nvar it = arrayview2iteratorRight( [ 1, 2, 3, 4 ], fcn );\n// returns \u003cObject\u003e\n\nvar v = it.next().value;\n// returns 40.0\n\nv = it.next().value;\n// returns 30.0\n\nv = it.next().value;\n// returns 20.0\n\n// ...\n```\n\nThe invoked function is provided four arguments:\n\n-   **value**: iterated value.\n-   **index**: iterated value index.\n-   **n**: iteration count (zero-based).\n-   **src**: source array-like object.\n\n```javascript\nfunction fcn( v, i ) {\n    return v * (i+1);\n}\n\nvar it = arrayview2iteratorRight( [ 1, 2, 3, 4 ], fcn );\n// returns \u003cObject\u003e\n\nvar v = it.next().value;\n// returns 16\n\nv = it.next().value;\n// returns 9\n\nv = it.next().value;\n// returns 4\n\n// ...\n```\n\nTo set the callback function execution context, provide a `thisArg`.\n\n```javascript\nfunction fcn( v ) {\n    this.count += 1;\n    return v * 10.0;\n}\n\nvar ctx = {\n    'count': 0\n};\n\nvar it = arrayview2iteratorRight( [ 1, 2, 3, 4 ], fcn, ctx );\n// returns \u003cObject\u003e\n\nvar v = it.next().value;\n// returns 40.0\n\nv = it.next().value;\n// returns 30.0\n\nv = it.next().value;\n// returns 20.0\n\nvar count = ctx.count;\n// returns 3\n```\n\n\u003c/section\u003e\n\n\u003c!-- /.usage --\u003e\n\n\u003c!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. --\u003e\n\n\u003csection class=\"notes\"\u003e\n\n## Notes\n\n-   If an environment supports `Symbol.iterator`, the returned iterator is iterable.\n-   If provided a generic `array`, the returned iterator does **not** ignore holes. To achieve greater performance for sparse arrays, use a custom iterator.\n-   A returned iterator does **not** copy a provided array-like `object`. To ensure iterable reproducibility, copy a provided array-like `object` **before** creating an iterator. Otherwise, any changes to the contents of an array-like `object` will be reflected in the returned iterator.\n-   In environments supporting `Symbol.iterator`, the function **explicitly** does **not** invoke an array's `@@iterator` method, regardless of whether this method is defined. To convert an array to an implementation defined iterator, invoke this method directly.\n-   The returned iterator supports array-like objects having getter and setter accessors for array element access (e.g., [`@stdlib/array-complex64`][@stdlib/array/complex64]).\n\n\u003c/section\u003e\n\n\u003c!-- /.notes --\u003e\n\n\u003c!-- Package usage examples. --\u003e\n\n\u003csection class=\"examples\"\u003e\n\n## Examples\n\n\u003c!-- eslint no-undef: \"error\" --\u003e\n\n```javascript\nvar Float64Array = require( '@stdlib/array-float64' );\nvar inmap = require( '@stdlib/utils-inmap' );\nvar randu = require( '@stdlib/random-base-randu' );\nvar arrayview2iteratorRight = require( '@stdlib/array-to-view-iterator-right' );\n\nfunction scale( v, i ) {\n    return v * (i+1);\n}\n\n// Create an array filled with random numbers:\nvar arr = inmap( new Float64Array( 100 ), randu );\n\n// Create an iterator from an array view which scales iterated values:\nvar it = arrayview2iteratorRight( arr, 40, 60, scale );\n\n// Perform manual iteration...\nvar v;\nwhile ( true ) {\n    v = it.next();\n    if ( v.done ) {\n        break;\n    }\n    console.log( v.value );\n}\n```\n\n\u003c/section\u003e\n\n\u003c!-- /.examples --\u003e\n\n\u003c!-- Section to include cited references. If references are included, add a horizontal rule *before* the section. Make sure to keep an empty line after the `section` element and another before the `/section` close. --\u003e\n\n\u003csection class=\"references\"\u003e\n\n\u003c/section\u003e\n\n\u003c!-- /.references --\u003e\n\n\u003c!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. --\u003e\n\n\u003csection class=\"related\"\u003e\n\n* * *\n\n## See Also\n\n-   \u003cspan class=\"package-name\"\u003e[`@stdlib/array-from-iterator`][@stdlib/array/from-iterator]\u003c/span\u003e\u003cspan class=\"delimiter\"\u003e: \u003c/span\u003e\u003cspan class=\"description\"\u003ecreate (or fill) an array from an iterator.\u003c/span\u003e\n-   \u003cspan class=\"package-name\"\u003e[`@stdlib/array-to-iterator-right`][@stdlib/array/to-iterator-right]\u003c/span\u003e\u003cspan class=\"delimiter\"\u003e: \u003c/span\u003e\u003cspan class=\"description\"\u003ecreate an iterator from an array-like object, iterating from right to left.\u003c/span\u003e\n-   \u003cspan class=\"package-name\"\u003e[`@stdlib/array-to-strided-iterator`][@stdlib/array/to-strided-iterator]\u003c/span\u003e\u003cspan class=\"delimiter\"\u003e: \u003c/span\u003e\u003cspan class=\"description\"\u003ecreate an iterator from a strided array-like object.\u003c/span\u003e\n-   \u003cspan class=\"package-name\"\u003e[`@stdlib/array-to-view-iterator`][@stdlib/array/to-view-iterator]\u003c/span\u003e\u003cspan class=\"delimiter\"\u003e: \u003c/span\u003e\u003cspan class=\"description\"\u003ecreate an iterator from an array-like object view.\u003c/span\u003e\n\n\u003c/section\u003e\n\n\u003c!-- /.related --\u003e\n\n\u003c!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. --\u003e\n\n\n\u003csection class=\"main-repo\" \u003e\n\n* * *\n\n## Notice\n\nThis package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.\n\nFor more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].\n\n#### Community\n\n[![Chat][chat-image]][chat-url]\n\n---\n\n## License\n\nSee [LICENSE][stdlib-license].\n\n\n## Copyright\n\nCopyright \u0026copy; 2016-2025. The Stdlib [Authors][stdlib-authors].\n\n\u003c/section\u003e\n\n\u003c!-- /.stdlib --\u003e\n\n\u003c!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. --\u003e\n\n\u003csection class=\"links\"\u003e\n\n[npm-image]: http://img.shields.io/npm/v/@stdlib/array-to-view-iterator-right.svg\n[npm-url]: https://npmjs.org/package/@stdlib/array-to-view-iterator-right\n\n[test-image]: https://github.com/stdlib-js/array-to-view-iterator-right/actions/workflows/test.yml/badge.svg?branch=main\n[test-url]: https://github.com/stdlib-js/array-to-view-iterator-right/actions/workflows/test.yml?query=branch:main\n\n[coverage-image]: https://img.shields.io/codecov/c/github/stdlib-js/array-to-view-iterator-right/main.svg\n[coverage-url]: https://codecov.io/github/stdlib-js/array-to-view-iterator-right?branch=main\n\n\u003c!--\n\n[dependencies-image]: https://img.shields.io/david/stdlib-js/array-to-view-iterator-right.svg\n[dependencies-url]: https://david-dm.org/stdlib-js/array-to-view-iterator-right/main\n\n--\u003e\n\n[chat-image]: https://img.shields.io/gitter/room/stdlib-js/stdlib.svg\n[chat-url]: https://app.gitter.im/#/room/#stdlib-js_stdlib:gitter.im\n\n[stdlib]: https://github.com/stdlib-js/stdlib\n\n[stdlib-authors]: https://github.com/stdlib-js/stdlib/graphs/contributors\n\n[umd]: https://github.com/umdjs/umd\n[es-module]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Modules\n\n[deno-url]: https://github.com/stdlib-js/array-to-view-iterator-right/tree/deno\n[deno-readme]: https://github.com/stdlib-js/array-to-view-iterator-right/blob/deno/README.md\n[umd-url]: https://github.com/stdlib-js/array-to-view-iterator-right/tree/umd\n[umd-readme]: https://github.com/stdlib-js/array-to-view-iterator-right/blob/umd/README.md\n[esm-url]: https://github.com/stdlib-js/array-to-view-iterator-right/tree/esm\n[esm-readme]: https://github.com/stdlib-js/array-to-view-iterator-right/blob/esm/README.md\n[branches-url]: https://github.com/stdlib-js/array-to-view-iterator-right/blob/main/branches.md\n\n[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/array-to-view-iterator-right/main/LICENSE\n\n[@stdlib/array/complex64]: https://github.com/stdlib-js/array-complex64\n\n\u003c!-- \u003crelated-links\u003e --\u003e\n\n[@stdlib/array/from-iterator]: https://github.com/stdlib-js/array-from-iterator\n\n[@stdlib/array/to-iterator-right]: https://github.com/stdlib-js/array-to-iterator-right\n\n[@stdlib/array/to-strided-iterator]: https://github.com/stdlib-js/array-to-strided-iterator\n\n[@stdlib/array/to-view-iterator]: https://github.com/stdlib-js/array-to-view-iterator\n\n\u003c!-- \u003c/related-links\u003e --\u003e\n\n\u003c/section\u003e\n\n\u003c!-- /.links --\u003e\n","funding_links":["https://github.com/sponsors/stdlib-js","https://opencollective.com/stdlib","https://tidelift.com/funding/github/npm/@stdlib/stdlib"],"categories":[],"sub_categories":[],"project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fstdlib-js%2Farray-to-view-iterator-right","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fstdlib-js%2Farray-to-view-iterator-right","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fstdlib-js%2Farray-to-view-iterator-right/lists"}