Got `maybeOut` wrong, can't edit, but it should be: maybeOut :: (a -> b) -> (a -... | Hacker News

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		itishappy on Sept 12, 2024 \| parent \| context \| favorite \| on: Why Haskell? Got `maybeOut` wrong, can't edit, but it should be: `maybeOut :: (a -> b) -> (a -> Maybe b) maybeOut = (.) Just` Also the parenthesis around the last two output types are added for emphasis, but can be safely removed.

itishappy on Sept 13, 2024 [–]

Last reply. Probably. Here's `maybe` in TypeScript:

    const maybe = <T,>(f: (_: T) => T, d:T) => (x: T|null) => f(x || d);

    console.log(maybe((x) => 2 * x, 3)(null)); // returns: 6

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