ResizeArrayT

ResizeArrayT is an F# extension and module library for ResizeArray<'T> ( = Collection.Generic.List<'T>).
It provides all the functions from the Array module in FSharp.Core for ResizeArray.
And more.

It also works in Javascript and Typescript with Fable.

This library was designed for use with F# scripting.
Functions and methods never return null.
When a function fails on invalid input it will throw a descriptive exception.
Functions starting with try... will return an F# option.

I was always annoyed that an IndexOutOfRangeException does not include the actual bad index nor the actual size of the array.
This library fixes that in the resizeArray.Get, resizeArray.Set, resizeArray.Slice and similar instance methods for item access.
I made a similar a similar library for array<'T>: https://github.com/goswinr/ArrayT/ .

Why ?

Yes, F#'s array and list modules can do these kind of operations on collections too.
But ResizeArray, being mutable, still offers the best performance for collections that can expand & shrink and need random access via an index.
In fact FSharp.Core uses a very similar module internally.

It Includes:

• A ResizeArray module that has all functions from [Array module from FSharp.Core] reimplemented (https://fsharp.github.io/fsharp-core-docs/reference/fsharp-collections-arraymodule.html).
  Including the sub module for Parallel computing.

• A Computational Expressions resizeArray that can be used like existing ones for seq.

• Support for F# slicing operator and indexing from the end. e.g: items.[ 1 .. ^1].

• Extension members on ResizeArray like .Get .Set .First .Last .SecondLast and more.
  With nicer IndexOutOfRangeExceptions that include the bad index and the actual size.

• All Tests from the from FSharp.Core's Array module ported and adapted to run in both javascript and dotnet.

Namespace

The main namespace is ResizeArrayT.
It was renamed from ResizeArray to ResizeArrayT in release 0.23. When used in scripting this helps avoid name collisions with the
module inside of the same name. [Reference Issue].(https://github.com/dotnet/fsharp/issues/17124)

Older versions of the library will still work with the old namespace ResizeArray.
And can be found on nuget.org with the name ResizeArray.

Usage

Just open the namespace

open ResizeArrayT

this namespace contains: - a module also called ResizeArray - a Computational Expressions called resizeArray - this will also auto open the extension members on ResizeArray<'T>

then you can do:

let evenNumbers =
    resizeArray {  // a Computational Expression like seq
        for i = 0 to 99 do
            if i % 2 = 0 then
                i
    }

let oddNumbers = evenNumbers |> ResizeArray.map (fun x -> x + 1) // ResizeArray module

let hundred = oddNumbers.Last // Extension member to access the last item in the list

Full API Documentation

goswinr.github.io/ResizeArrayT

Tests

All Tests run in both javascript and dotnet. Successful Fable compilation to typescript is verified too. Go to the tests folder:

cd Tests

For testing with .NET using Expecto:

dotnet run

for JS testing with Fable.Mocha and TS verification:

npm test

License

MIT

Changelog

see CHANGELOG.md