fsil: F# inline library

Features:

• a small generic utils library like FSharpPlus
• all functions are inline and trimmable, won't bloat your binary size: you pay for only what you use
• Fable compatible
• zero cost: does not create junk variables or implicit allocations
• uses [<AutoOpen>] so all functions are in the global namespace

Example:

Benchmark comparisons to FSharpPlus

I love F# for high performance programming and this makes high-level generic F# a little more feasible without punishing the user performance-wise. The functions in this library compile down to exactly the same form as the (optimal) resolved implementation so iter f x to the compiler is identical to e.g., ValueOption.iter f x or Array.iter f x.

Currently this library contains a fairly small set of functions:

iter, iteri, iter_range, map, mapi, is_some, is_none, is_ok, some, none, try_item, value, len, enum, enumv, default_, default_inst, default_with, zero, one, print, forall, exists, fold, foldi.

there are also some functions for spans with separate function definitions due to their limitations:

span_forall, span_exists, span_iter...

You can also define your own implementations as static members. here is an example for iter and map on a Tree, for documentation just look at the source code itself.

type Tree<'T> =
    | Leaf of 'T
    | Node of 'T * Tree<'T> * Tree<'T>

    static member Map(self: Tree<'T>, fn: 'T -> 'U) : Tree<'U> =
        match self with
        | Leaf x -> Leaf(fn x)
        | Node(v, l, r) ->
            let new_l = Tree.Map(l, fn)
            let new_r = Tree.Map(r, fn)
            Node(fn v, new_l, new_r)

    static member Iterate(self: Tree<'T>, fn: 'T -> unit) : unit =
        match self with
        | Leaf x -> fn x
        | Node(v, l, r) ->
            Tree.Iterate(l, fn)
            fn v
            Tree.Iterate(r, fn)

let tree1 = Leaf 1
let iter = tree1 |> iter (fun v -> print v)
let mapped: Tree<int> = tree1 |> map (fun v -> v + 1)
// these implementations are generated from Iterate and Map
// so you get them "for free"
let iteri = tree1 |> iteri (fun idx v -> print v)
let mapped2: Tree<int> = tree1 |> mapi (fun idx v -> idx + v + 1)
let sum = tree1 |> fold 0 (fun acc v -> acc + 1 )
let sum2 = tree1 |> foldi 0 (fun idx acc v -> acc + 1 )

Most important remember to have (f#)un! :)