## to-property-key-x
Converts argument to a value that can be used as a property key.
**Version**: 2.0.2
**Author**: Xotic750
**License**: [MIT](<https://opensource.org/licenses/MIT>)
**Copyright**: Xotic750
### `module.exports(argument)` ⇒ string \| symbol ⏏
This method Converts argument to a value that can be used as a property key.
**Kind**: Exported function
**Returns**: string \| symbol - The converted argument.
**Throws**:
- TypeError If argument is not a symbol and is not coercible to a string.
| Param | Type | Description |
| --- | --- | --- |
| argument | \* | The argument to onvert to a property key. |
**Example**
```js
var toPropertyKey = require('to-property-key-x');
toPropertyKey(); // 'undefined'
toPropertyKey(1); // '1'
toPropertyKey(true); // 'true'
var symbol = Symbol('a');
toPropertyKey(symbol); // symbol
toPropertyKey(Object.create(null)); // TypeError
```