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karolk/proto-version.js

Last active June 7, 2018 10:34
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versions in prototype chain
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proto-version.js
// IDEA: start with an object using a symbol as a marker
const create = (obj, changeSet) => Object.assign(Object.create(obj || {[Symbol.for('versionstart')]: true}), changeSet);
const getPreviousState = obj => {
const maybePrev = Object.getPrototypeOf(obj);
if (!maybePrev || maybePrev[Symbol.for('versionstart')]) {
return null;
}
return maybePrev;
}
// TODO how do we know how many versions we have?
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