But – A way to pass along a callback with just a single argument

Re:But – A way to pass along a callback with just a single a... by nilved on Monday December 29, 2014 @03:28PM (#8811600)

When you use `console.log` that way it gets `this` set to `null`. When you call `console.log("hello")`, `this` is set to `console`. Your code would work if you set an explicit `this`.

    n.forEach(console.log.bind(console));

I don't think there's any reason for this library to exist after you understand `this` semantics but I may be missing something.

e: was, in fact, missing something. Apologies for the disparaging comment, see replies.

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Re:But – A way to pass along a callback with just a single a... by willyg302 on Monday December 29, 2014 @03:35PM (#8811634)

Additionally, this will log all the passed arguments (value, index, and array being traversed), which typically isn't what you want:

    [1, 2, 3].forEach(console.log.bind(console));
    > 1 0 [1, 2, 3]
    > 2 1 [1, 2, 3]
    > 3 2 [1, 2, 3]

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Re:But – A way to pass along a callback with just a single a... by dyscrete on Monday December 29, 2014 @03:32PM (#8811623)

Well it's not just about `this` but the arguments to pass to console rather. In this case:

    n.forEach(console.log.bind(console));

forEach is passing console all of its callback arguments, resulting in logging of keys, values, and array.

EDIT: Forgot array

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Re:But – A way to pass along a callback with just a single a... by nilved on Monday December 29, 2014 @03:55PM (#8811716)

Ah, I understand. It reminds me of how the `cut` function could be used in Scheme.

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Re:But – A way to pass along a callback with just a single a... by aaronem on Monday December 29, 2014 @03:59PM (#8811739)

Convenience, I suppose; I had a few headaches when I first transitioned to Javascript and discovered the odd signatures its collection functions' callbacks are expected to have.

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Re:But – A way to pass along a callback with just a single a... by bevacqua on Monday December 29, 2014 @03:30PM (#8811609)

That's one, the other is that many of those functional methods tend to mess with functions that take more than one argument when you want to use the first one, e.g parseInt.

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