Elm Syntax

BasicSyntax.elm

module BasicSyntax exposing (..)

fact : Int -> Int
fact n =
    if n == 0 then
        1
    else
        n * fact (n - 1)
        
map : (a -> b) -> List a -> List b
map fn vals =
    case vals of
        [] ->
            []
         v :: vs ->
            (fn v) :: map fn vs
squares =
    let
        sqfn =
            (\x -> x * x)
    in
        map sqfn ([ 1, 2, 3 ] ++ [ 4, 5, 6 ])

type alias Model =
    { user : Maybe User
    , state : UIState
    , size : ( Int, Int )
    }

type UIState
    = Sizing
    | LogIn
    | Loading
    | Ready

vals : List { a | val : Int } -> List Int
vals vs =
    map .val vs

noSubtyping =
    -- a is {} in 1, and a is { bad : True} in 2, so will fail type checking
    vals [ { val = 2 }, { val = 3, bad = True } ]

type Maybe a
    = Nothing
    | Just a

divByZero =
    4 // 0

floatDivByZero =
    4.0 / 0.0