linq-es6

    0.2.1 • Public • Published

    LINQ in JavaScript

    I write a lot of C# and it has a really useful way to query large collections of data, called LINQ.

    Although JavaScript arrays have querying capabilities through map, reduce, filter but the limitation is they process the entire array before going to the next step, meaning if you do a map then a filter the whole collection goes through map process before it starts filtering. This can be a problem with large data sets, it can take a while.

    Why LINQ?

    The advantage of LINQ is that it uses lazy execusion, each item goes through the whole pipeline before the next item is processed. So if you have a large data set you can easily process subsets of the data and break early.

    How does it work?

    To do this it leverages the ES6 Iterators to yield each value.

    Example

    var items = [1, 2, 3, 4, 5, 6].asEnumerable();
    
    for (let item in items.where(x => x % 2).select(x => x + 1))
        console.log(item);
    
    //output will be 2, 4, 6
    

    API

    The following LINQ methods are implemented:

    • aggregate
    • all
    • any
    • asEnumerable
    • average
    • concat
    • contains
    • count
    • first, firstOrDefault
    • range
    • repeat
    • select, aliased to map
    • selectMany
    • single, singleOrDefault
    • toArray
    • where, aliased to filter

    The full list of what LINQ in .NET does can be found here.

    License

    MIT

    Keywords

    none

    Install

    npm i linq-es6

    DownloadsWeekly Downloads

    38

    Version

    0.2.1

    License

    MIT

    Last publish

    Collaborators

    • aaronpowell