utils.fromJS

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> This package is intended for consumption via the [@profiscience/knockout-contrib] metapackage

Usage

> fromJS(src[, mapArrayElements = false])

Creates a tree of observables from src.

If mapArrayElements is true, array elements will be passed to fromJS as well, else bare objects/primitives.

The much needed inverse to the undocumented ko.toJS function; a dumb version of ko.mapping.fromJS that is _a lot faster_.

``javascript
import { fromJS } from '@profiscience/knockout-contrib'

const foos = {
foo: 'foo',
bar: {
baz: 'baz',
qux: ['qux'],
},
}

fromJS(foos)
// {
// foo: ko.observable('foo'),
// bar: {
// baz: ko.observable('baz'),
// qux: ko.observableArray([
// 'qux'
// ])
// }
// }

fromJS(foos, true)
// {
// foo: ko.observable('foo'),
// bar: {
// baz: ko.observable('baz'),
// qux: ko.observableArray([
// ko.observable('qux') <--------- Array contents mapped when second argument is true
// ])
// }
// }
`

Benchmark

`shell
$ ./benchmark.ts
utils.fromJS x 316,313 ops/sec ±3.37% (79 runs sampled)
utils.fromJS (mapArrayElements) x 151,401 ops/sec ±3.24% (81 runs sampled)
mapping.fromJS x 11,995 ops/sec ±3.82% (81 runs sampled)
``