npm package discovery and stats viewer.

Discover Tips

  • General search

    [free text search, go nuts!]

  • Package details

    pkg:[package-name]

  • User packages

    @[username]

Sponsor

Optimize Toolset

I’ve always been into building performant and accessible sites, but lately I’ve been taking it extremely seriously. So much so that I’ve been building a tool to help me optimize and monitor the sites that I build to make sure that I’m making an attempt to offer the best experience to those who visit them. If you’re into performant, accessible and SEO friendly sites, you might like it too! You can check it out at Optimize Toolset.

About

Hi, 👋, I’m Ryan Hefner  and I built this site for me, and you! The goal of this site was to provide an easy way for me to check the stats on my npm packages, both for prioritizing issues and updates, and to give me a little kick in the pants to keep up on stuff.

As I was building it, I realized that I was actually using the tool to build the tool, and figured I might as well put this out there and hopefully others will find it to be a fast and useful way to search and browse npm packages as I have.

If you’re interested in other things I’m working on, follow me on Twitter or check out the open source projects I’ve been publishing on GitHub.

I am also working on a Twitter bot for this site to tweet the most popular, newest, random packages from npm. Please follow that account now and it will start sending out packages soon–ish.

Open Software & Tools

This site wouldn’t be possible without the immense generosity and tireless efforts from the people who make contributions to the world and share their work via open source initiatives. Thank you 🙏

© 2024 – Pkg Stats / Ryan Hefner

@stdlib/iter-pop

v0.2.1

Published

Create an iterator which skips the last value of a provided iterator.

Downloads

214

Readme

iterPop

NPM version Build Status Coverage Status

Create an iterator which skips the last value of a provided iterator.

Installation

npm install @stdlib/iter-pop

Usage

var iterPop = require( '@stdlib/iter-pop' );

iterPop( iterator[, clbk[, thisArg]] )

Returns an iterator which skips the last value of a provided iterator.

var array2iterator = require( '@stdlib/array-to-iterator' );

var it = iterPop( array2iterator( [ 1, 2, 3, 4 ] ) );
// returns <Object>

var v = it.next().value;
// returns 1

v = it.next().value;
// returns 2

v = it.next().value;
// returns 3

var bool = it.next().done;
// returns true

The returned iterator protocol-compliant object has the following properties:

  • 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.
  • return: function which closes an iterator and returns a single (optional) argument in an iterator protocol-compliant object.

To invoke a callback upon skipping the last value of a provided iterator, provide a clbk argument.

var array2iterator = require( '@stdlib/array-to-iterator' );

function onPop( v ) {
    console.log( v );
    // => 4
}

var it = iterPop( array2iterator( [ 1, 2, 3, 4 ] ), onPop );
// returns <Object>

var v = it.next().value;
// returns 1

v = it.next().value;
// returns 2

v = it.next().value;
// returns 3

var bool = it.next().done;
// returns true

The callback function is provided a single argument:

  • v: the skipped value

To set the callback execution context, provide a thisArg.

var array2iterator = require( '@stdlib/array-to-iterator' );

function onPop() {
    this.count += 1;
}

var ctx = {
    'count': 0
};

var it = iterPop( array2iterator( [ 1, 2, 3, 4 ] ), onPop, ctx );
// returns <Object>

var v = it.next().value;
// returns 1

v = it.next().value;
// returns 2

v = it.next().value;
// returns 3

var bool = it.next().done;
// returns true

bool = ( ctx.count === 1 );
// returns true

Notes

  • If an environment supports Symbol.iterator and a provided iterator is iterable, the returned iterator is iterable.

Examples

var randu = require( '@stdlib/random-iter-randu' );
var iterPop = require( '@stdlib/iter-pop' );

// Create a seeded iterator for generating pseudorandom numbers:
var rand = randu({
    'seed': 1234,
    'iter': 10
});

// Create an iterator which skips the last number:
var it = iterPop( rand );

// Perform manual iteration...
var v;
while ( true ) {
    v = it.next();
    if ( v.done ) {
        break;
    }
    console.log( v.value );
}

See Also

  • @stdlib/iter-push: create an iterator which appends additional values to the end of a provided iterator.
  • @stdlib/iter-shift: create an iterator which skips the first value of a provided iterator.
  • @stdlib/iter-slice: create an iterator which returns a subsequence of iterated values from a provided iterator.

Notice

This package is part of 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.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

Community

Chat


License

See LICENSE.

Copyright

Copyright © 2016-2024. The Stdlib Authors.