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@jimbolla
Created November 16, 2015 19:38
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protectFromUnmount
function protectFromUnmount() {
let callbacks = {};
let count = 0;
const noop = value => value;
const wrapCallback = id => function(...params) {
const raceSafeCallbacks = callbacks;
if (!raceSafeCallbacks)
return noop(...params);
const callback = raceSafeCallbacks[id];
delete raceSafeCallbacks[id];
return callback(...params);
};
const protect = (callback) => {
const raceSafeCallbacks = callbacks;
if (!raceSafeCallbacks)
return noop;
const id = count++;
raceSafeCallbacks[id] = callback;
return wrapCallback(id);
};
protect.unmount = () => callbacks = null;
return protect;
}
@istarkov
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What the idea of this raceSafeCallbacks
What the situation you will need them?

This is enough

function protectFromUnmount() {
    let hasUnmounted_ = false;

    const protect = (callback) => {
        return (...args) => !hasUnmounted_ && callback(...args);
    };

    protect.unmount = () => hasUnmounted_ = true;

    return protect;
}

@Dottenpixel
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This is great. Tagging this with the GitHub issue that brought me here.

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