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Comment by minitech | Hacker News Reader

Personal opinion: none of the syntax or results in your blog post were confusing, other than square brackets looking confusingly like curly braces in the font. It’s how splat works in every language I’ve used. “This operation that doesn’t make sense doesn’t work” especially not confusing.

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Re-read that post and the idea that this is perfectly fine parenthesis redundancy:

    A = 'hello world'
    console.log( A )   // prints 'hello world'
    console.log( (A) ) // also prints 'hello world'

But this breaks with a random-ass error because of how arrow functions interact with `...rest` parameters

    A = ['hello', 'world']
    console.log( ...A )   // prints 'hello world'
    console.log( (...A) ) // SyntaxError: expected '=>' after argument list, got ')'

Is still absolutely hilarious and reeks of "design by committee."

I read that fine the first time. It’s exactly the behaviour I would expect and would have specced. Splat as an actual operator doesn’t make sense; it’d have to produce some kind of horrible magic value.

Engines might be able to improve the error message, but I can’t say I’ve ever run into that one.

It's easier to see what's going on when you consider the spread operator to be an operator working on the function not the parameters:

    const dotdotdot = <A>(f: Function) => (list: Array<A>) => f.apply(this, list)

    dotdotdot(console.log)([10, 20, 30])
    console.log(...[10, 20, 30])

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