PoC of let?

[zth]

npm i https://pkg.pr.new/rescript-lang/rescript@7582

let getXWithResultAsync = async s => {
  let? Ok({s} as res) = await doStuffResultAsync(s)
  Console.log(s)
  let? Ok(x) = await decodeResAsync(res)
  Ok(x ++ "test")
}

TODO

• Make sure error messages make sense and are well covered
• Make sure editor tooling works as expected

[pkg-pr-new]

Open in StackBlitz

rescript

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@rescript/darwin-arm64

npm i https://pkg.pr.new/rescript-lang/rescript/@rescript/darwin-arm64@7582

@rescript/darwin-x64

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@rescript/linux-arm64

npm i https://pkg.pr.new/rescript-lang/rescript/@rescript/linux-arm64@7582

@rescript/linux-x64

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@rescript/win32-x64

npm i https://pkg.pr.new/rescript-lang/rescript/@rescript/win32-x64@7582

commit: 279c248

[leoliu]

Looks like a great feature in development!

BTW some languages place ? around the = like ?= or =?. I wonder if this has been considered. This can potentially also be used with if.

[zth]

@leoliu thank you! There's now a forum post for the proposal where you can add your thoughts if you want: https://forum.rescript-lang.org/t/proposing-new-syntax-for-zero-cost-unwrapping-options-results/6227