F# Flexible Types example out of date

[LePelicaN]

The F# documentation about flexible-types.md is not up to date with the latest F# version.

The example states:

let iterate1 (f : unit -> seq<int>) =
    for e in f() do printfn "%d" e
let iterate2 (f : unit -> #seq<int>) =
    for e in f() do printfn "%d" e

// Passing a function that takes a list requires a cast.
iterate1 (fun () -> [1] :> seq<int>)

// Passing a function that takes a list to the version that specifies a
// flexible type as the return value is OK as is.
iterate2 (fun () -> [1])

But since F#6 and the RFC FS-1093, the cast is not required and the following line works:

iterate1 (fun () -> [1])

I can propose an update through a PR but I don't know if I should rather:

• Keep this example but emphasize that it's only relevant before F#6.
• Remove it and only keep the relevant seq.concat example.

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Document Details

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• ID: 801ffa68-e3b2-71e7-03e4-1f5ab606e579
• Version Independent ID: a64255fa-049b-02a2-5261-11d675688033
• Content: Flexible Types - F#
• Content Source: docs/fsharp/language-reference/flexible-types.md
• Product: dotnet-fsharp
• GitHub Login: @cartermp
• Microsoft Alias: dotnetcontent