F# Basics

Getting started with functional-first programming

Why F#?

F# is a functional-first language that runs on .NET with excellent tooling and library support.

Immutable by default, powerful type inference, and elegant syntax

Full access to the .NET ecosystem and C# interoperability

// Simple F# console application
open System

[]
let main argv =
    printfn "Hello %s" (String.Join(" ", argv))
    0 // return exit code

> let square x = x * x;;
val square: x:int -> int

> square 5;;
val it: int = 25

Use F# Interactive (FSI) for rapid prototyping and testing.