Capturing variables in F# loop

[Jand42]

The for i = ... currently checks if the index variable's value is captured, but capturing another variable in a block does not get correctly scoped. Example:

let arr = [| 1 .. 10 |]
let funcs = ResizeArray()
let res = ResizeArray()
do
for i in [| 0 .. 9 |] do
    let j = arr.[i]
    funcs.Add(fun () -> res.Add j)
for f in funcs do
    f()

Running the JavaScript translation, the result of res is currently repeating 10, because a single j variable is captured in the created functions, which is not correct semantics for F#.

[Jand42]

This is now handled properly in WebSharper 4. Test: https://github.com/dotnet-websharper/websharper/blob/5d62d6730f3cf126d649aa043dac74fb768342c5/tests/WebSharper.Tests/Regression.fs#L449-L460