const add = (state, { payload }) => {
return state.concat(payload);
};
const add = (state, { payload }) => {
return state.concat(payload);
};
function is a member of the object, the deconstruction assignment takes precedence.
/ / bad
function getFullName (user) {
const firstName = user.firstName;
const lastName = user.lastName;
}
/ / good
function getFullName (obj) {
const {firstName, lastName} = obj;
}
/ / best
function getFullName ({firstName, lastName}) {
}
getting started with ECMAScript 6
two parameters: one is state, the other is an object taking out the value of the payload field in the object and assigning it to the payload variable. The second is an object deconstructing
// .
add(['a','b'], {payload:['c','d']}) // ['a','b','c','d']
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