object-access
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Access(read, write and delete) an object by hierarchical keys.
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Access(read, write and delete) an object by hierarchical keys. And it can be used as an alternative for the null propagation operator
```js
const access = require('object-access')
const obj = {
one: {
two: 2
}
}
```
If we use a null operator like many other languages and the [tc39 proposal](https://docs.google.com/presentation/d/11O_wIBBbZgE1bMVRJI8kGnmC6dWCBOwutbN9SWOK0fU/view#slide=id.g1c161255c9_0_55)
```js
// Use Null Propagation Operator
obj.one?.two // 2
// Use object-access
access(obj, 'one.two', 2)) // 2
```
```js
// Get
access(obj, 'one.two') // 2
access(obj, ['one', 'two']) // 2
access(obj, ['one', 'three']) // undefined
access(obj, ['one', 'three', 'four']) // undefined
access(obj, ['one', 'three', 'four'], 4) // 4
// Set
access.set(obj, 'one.two', 3) // 3
// then obj.one.two.three is 3
access.set(obj, ['one', 'two'], 4) // 4
// then obj.one.two.three is 4
// If the subtle object is not found, it will create one
access.set(obj, ['three', 'four'], 6) // 6
// then obj.three.four is 6
// If we try to set a property on a none-object value, it will thrown.
access.set(obj, 'one.two.tree', 3) // Error thrown!
// Force setting
access.set(obj, 'one.two.tree', 3, true) // true
// obj.one.two is {three: 3}
access.delete(obj, 'one.two.four') // obj.one.two.four -> undefined
access.delete(obj, 'one.two.tree') // obj.one.two -> {}
access.delete(obj, 'one.two') // obj.one -> {}
```
Get value
- obj `Object`
- key_list `Array|string` see the example above
- default_value `any=` if key_list not found, then returns the `default_value`, if `default_value` is not specified, `undefined` will be returned.
If the property already exists and is not an object, `access.set()` will throw an error whose `code` is `SET_ON_NONE_OBJECT`.
If you want to force setting new values on none object value and override it, or to prevent any errors, use `force=true`.
Returns `value`
Removes a key by deleting it if exists.
Returns `true` if succeeded otherwise `false`
Method | `1.x` | `2.x`
---- | ---- | ----
set | no return value | has return value if there is no error
set | never thrown | thrown if you try to set property on none object
remove | no return value | has return value
MIT