I have the following structure in the project im working on (uses immutable JS):
data :[{name: 'john', surname: 'smith', children: [{name: 'sam'}, {name: 'ben'}]}, {name: 'jane', surname: 'jones', children: [{name: 'tim'}, {name: 'amy'}]}]
the object is converted to immutable JS via fromJS().
I need a new object in the following structure:
data :[{name: 'john', surname: 'smith', children: ['sam','ben']}, {name: 'jane', surname: 'jones', children: ['tim','amy']}]
Any pointers much appreciated.
The pure JS answer of Christian doesn't exactly apply to immutable.js objects, so here are a few ways to do it with immutable.js's collection API.
There are more options (e.g. reduce
), feel free to check the docs; the method descriptions usually come with examples.
const raw = [{name: 'john', surname: 'smith', children: [{name: 'sam'}, {name: 'ben'}]},
{name: 'jane', surname: 'jones', children: [{name: 'tim'}, {name: 'amy'}]}];
const data = Immutable.fromJS(raw);
function run(name, operation) {
let result;
console.time(name);
for(let i=0; i < 50000; i++){
result = operation();
}
console.timeEnd(name);
console.log(result1.toJS());
}
run('simple', () => {
// simply updating objects inside a mapping
result1 = data.map(
person => person.update('children',
kidObjs => kidObjs.map(
kid => kid.get('name')
)
)
);
});
run('withMutations and setIn', () => {
// using withMutations and setIn
result2 = data.withMutations(list => {
list.forEach((val, idx) => {
list.setIn(
[idx, 'children'],
val.get('children').map(kid => kid.get('name'))
)
});
});
});
run('withMutations and update', () => {
// slightly faster by using withMutations set/update
result2 = data.withMutations(list => {
list.forEach((val, idx) => {
list.set(idx, val.update('children', kids => kids.map(kid => kid.get('name'))))
});
});
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/immutable/4.0.0-rc.14/immutable.min.js"></script>