F# friendly .Net

Making interaction with the .Net Api feel much more natural and friendlier for the eye.

In-depth ramblings here

Typical problems when interacting with the .Net api are

• Dealing with null's and try-methods feels wrong when we have Option in F#. An example of a try-method is int.Parse()
• KeyValuePair<> makes sense in C#, but is more naturally expressed at tuples in F#
• C# has automatic type conversion, F# doesn't - this makes calling some code look ridiculous
• Some actions are verbose done purely in F# (such as using sprintf)

The goals of this project are

• By defining a set of helper functions, we can make the interaction much smoother and generally making the coding experince better.
• When defining the helper methods, we can rectify or make clearer the existing .Net api.

Examples

For example turning an int i into a string s one can do

let i = 4
let s1 = i.ToString()    // I dont like the parenthesis and it feels non-functional
let s2 = sprintf "%d" i  // involves lots of shift-key pressing and little autocompletion
let s3 = toString i      // functional style and terse

clearly the s3 version is the less verbose and most functional.. and a part of this library.

Or how about turning try-method matching like

match int.TryParse(httpParameter) with
| true, x -> x
| false, _ -> ...

into something that returns Option like

match int.tryParse httpParameter with // using this library
| Some x -> x
| None -> ...

The missing type conversions in F# make for some really odd looking code. Just look at the TimeSpan api. Most of the TimeSpan methods take a double as an argument. I have yet to find a situation where you want to use a double as an argument. Pop quiz: What is the result of TimeSpan.FromMinutes(0.12345) ? Answer 00:00:07.4070000 (Microsoft). Are you kidding me Microsoft? Seriously? Please allow me to only use integers.

TimeSpan.FromMinutes(1.0)   // original
TimeSpan.fromMinutes 1      // using this library

Documentation

Here is the full documentation of the package. See also the code, it is pretty-self documenting anyways :-)

System

Implementations: System.fs

How to access this below code

String parsing

nicer tryParse methods that return Option<'T> rather than (bool * 'T)

• Boolean.tryParse s:string -> bool option
• Dobule.tryParse s:string -> float option
• Int32.tryParse s:string -> int option
• Int64.tryParse s:string -> int64 option
• Guid.tryParse s:string -> Guid option
• DateTime.tryParse s:string -> DateTime option

Also there are active patterns declared for conversion

let str = "8284784593947573344"
      let conv = match str with
                 | Int i -> "is int"
                 | Int64 i -> "is int64"
                 | Float f -> "is float"
                 | Bool b -> "is bool"
                 | _ -> invalidArg str "should be something"
 // conv -> "is int64"

Getting the package

The package is found on nuget. Use any of the following

Install-Package FSharpFriendlyDotNet  

or

dotnet add package FSharpFriendlyDotNet 

or

paket add FSharpFriendlyDotNet