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MatthewPhillips | karma 10535 | avg karma 3.19 · 2013-08-15 19:08:03+00:00

You could use const all over the place.

AlexanderDhoore | karma 2285 | avg karma 5.47 · 2013-08-15 19:16:32+00:00

Still doesn't give you immutable data structures though. For example:

    const myArray = [42];
    myArray.push("Oh noes");

    [42, "Oh noes"]

MatthewPhillips | karma 10535 | avg karma 3.19 · 2013-08-15 19:17:12+00:00

Ugh, you're kidding?

EDIT: checked in Node, yep. That's unfortunate. Can we get a let foo immutable = [1]; or something?

EDIT2: Although this can be implemented in user-land with Object.freeze. Create a function that returns a const that is frozen if it is non-primitive. That should cover it, right?

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kevingadd | karma 14699 | avg karma 2.67 · 2013-08-15 19:43:57+00:00

freeze/seal don't actually provide true immutability in JS. There are cases where a frozen object can still be modified (Date is one of them, IIRC typed arrays are another)

tensor | karma 5723 | avg karma 3.71 · 2013-08-15 21:20:08+00:00

ClojureScript provides truly immutable data structures that compile down to javascript. You can use them from JS:

https://github.com/swannodette/mori

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