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Generic Peano arithmetic
An attempt at defining Peano arithmetic for all numeric types
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let inline zero () : ^T = LanguagePrimitives.GenericZero< ^T>
let inline succ (x : ^T) = x + LanguagePrimitives.GenericOne< ^T> : ^T
let inline incr (x : ^T ref) = x := succ !x
let inline infiniteSeq (x : ^T) =
let rec infinite x = seq { yield x ; yield! infinite (succ x) }
infinite x
infiniteSeq 42 > Seq.take 5 > Seq.toArray
infiniteSeq 3.14 > Seq.take 10 > Seq.toArray
type Peano = Zero  Succ of Peano
with
static member (+) (x : Peano, y : Peano) =
let rec add x = function Zero > x  Succ y > add (Succ x) y
add x y
static member One = Succ Zero
infiniteSeq Zero > Seq.take 10 > Seq.toArray

val zero : unit > 'T (requires member get_Zero)
Full name: Script.zero
module LanguagePrimitives
from Microsoft.FSharp.Core
val GenericZero<'T (requires member get_Zero)> : 'T (requires member get_Zero)
Full name: Microsoft.FSharp.Core.LanguagePrimitives.GenericZero
val succ : x:'T > 'T (requires member ( + ) and member get_One)
Full name: Script.succ
val x : 'T (requires member ( + ) and member get_One)
val GenericOne<'T (requires member get_One)> : 'T (requires member get_One)
Full name: Microsoft.FSharp.Core.LanguagePrimitives.GenericOne
val incr : x:'T ref > unit (requires member ( + ) and member get_One)
Full name: Script.incr
val x : 'T ref (requires member ( + ) and member get_One)
Multiple items
val ref : value:'T > 'T ref
Full name: Microsoft.FSharp.Core.Operators.ref

type 'T ref = Ref<'T>
Full name: Microsoft.FSharp.Core.ref<_>
val infiniteSeq : x:'T > seq<'T> (requires member ( + ) and member get_One)
Full name: Script.infiniteSeq
val infinite : ('T > seq<'T>) (requires member ( + ) and member get_One)
Multiple items
val seq : sequence:seq<'T> > seq<'T>
Full name: Microsoft.FSharp.Core.Operators.seq

type seq<'T> = System.Collections.Generic.IEnumerable<'T>
Full name: Microsoft.FSharp.Collections.seq<_>
module Seq
from Microsoft.FSharp.Collections
val take : count:int > source:seq<'T> > seq<'T>
Full name: Microsoft.FSharp.Collections.Seq.take
val toArray : source:seq<'T> > 'T []
Full name: Microsoft.FSharp.Collections.Seq.toArray
type Peano =
 Zero
 Succ of Peano
static member One : Peano
static member ( + ) : x:Peano * y:Peano > Peano
Full name: Script.Peano
union case Peano.Zero: Peano
union case Peano.Succ: Peano > Peano
val x : Peano
val y : Peano
val add : (Peano > Peano > Peano)
static member Peano.One : Peano
Full name: Script.Peano.One
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