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<?xml version="1.0" encoding="UTF-8" ?>
<dt-api group="static">
<name>DataTable.util.get()</name>
<summary>Create a read function from a descriptor</summary>
<since>1.11.0</since>
<type type="function">
<signature>get( descriptor )</signature>
<description>Build an accessor function to get data based on the given descriptor.</description>
<param type="string|object|function|null" name="descriptor">
A descriptor that is used to define how to read the data from the source object. See above for full details of the options that this can be used as.
</param>
<returns type="Function">An accessor function that will be used to read data from a given object</returns>
</type>
<description>
It can often be useful in Javascript to write data location descriptors as a string, as we often do with JSON notation - e.g. `staff.name`, or having the flexibility of using a function to get arbitrary data. The DataTables `-init columns.data` and `-init columns.render` properties make use of this to be able to easily describe where data should be fetched from to display in a column. This method exposes that ability as part of the DataTables API for use in plug-ins and other libraries.
The key point with this method is to remember that it will itself return a function, which you must then execute to be able to read the nested data - e.g.:
```js
let fn = DataTable.util.get('name.first');
let name = fn({
name: {
first: 'Fiona',
last: 'Grayling'
}
}); // Returns `Fiona`
```
The descriptor can be given as:
* `null`: The returned function will simply be return the full data object given to the accessor function.
* A function: Returns a function that will call the given function with the same parameters given to it (effectively just making it a proxy function).
* An object: Returns a function that will access data from an object based on the second parameter passed into the accessor. In DataTables this is used for the `-init columns.render` property's ability to use orthogonal data in an object.
* A string: Returns a function that will access data based on a JSON notation string, with the additional ability of being able to use `()` notation to execute a function, and `[]` to get array details. If `[]` is used without characters inside it for accessing an array, an array will be returned; if characters are used inside the brackets, they will be used to join the array - e.g. `[, ]` would give a comma space separated string.
</description>
</dt-api>
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