FSharp.Base

This projects contains code that I found myself writing more often than I wanted to. It contains a lot of extension methods for collections (lists, arrays, seq) and option types. Please note that most of the Array and Seq methods are simply wrappers around the list version. I have not found the time to write unique implementations (yet). There are tests for all functions (except trivial ones and the array/seq wrappers).

Usage

To use the extension methods for list, array or seq simply add the following import:

open b0wter.FSharp.Collections

You are then able to call the new methods like any other list method:

let first, second = myItems |> List.half

Using the option extension methods works the same:

open b0wter.FSharp
let result = myStringOption |> Option.getOrElse "defaultValue"

Custom Operators

I've defined some custom operators for tasks I found myself doing over and over. First, import:

open b0wter.FSharp.Operators

You'll then have access to:

|?  = Option.orElse
|?| = defaultArg
|=  = Option.compareIfSome
|=| = Option.compare

Lense

This package contains a very simple implementation of lenses. I've not written it myself. It's taken from here. I like this implementation because it's small and easy to use. However, due to its reliance on reflection it is slower than other options out there.

Here is how you use it:

type Human  = {Name:string}
and  Seat   = {Number:int; UsedBy:Human option}
and  Bus    = {DriverSeat:Seat}
and  Company= {Name:string;SchoolBus:Bus}

let BusDriver = {Human.Name="BusDriver A."}
let SchoolBus = {DriverSeat={Seat.Number=1;UsedBy=Some BusDriver}}
let BusCompany= {SchoolBus=SchoolBus; Name="EasyBus"}
    
do printfn "company: %A" BusCompany
// company: {Name = "EasyBus"; SchoolBus = {DriverSeat = {
//  Number = 1; UsedBy = Some {Name = "BusDriver A.";};};};}
do printfn "swapDriver: %A" <| Lens.With <@ BusCompany.SchoolBus.DriverSeat.UsedBy @> (Some {Human.Name="BusDriver Z."})
// swapDriver: {Name = "EasyBus"; SchoolBus = {DriverSeat = {
//  Number = 1; UsedBy = Some {Name = "BusDriver Z.";};};};}
do printfn "rmDriver: %A" <| Lens.With <@ BusCompany.SchoolBus.DriverSeat.UsedBy @> None
// rmDriver: {Name = "EasyBus"; SchoolBus = {DriverSeat = {
//  Number = 1; UsedBy = null;};};}
do printfn "mvSeat: %A" <| Lens.With <@ BusCompany.SchoolBus.DriverSeat.Number @> 12345
// mvSeat: {Name = "EasyBus"; SchoolBus = {DriverSeat = {
//  Number = 12345; UsedBy = Some {Name = "BusDriver A.";};};};}