insteadof operator

Bucaran jbucaran at me.com
Thu Jun 25 22:41:08 UTC 2015


Sometimes you have a function that receives a parameter shadowing an existing function or variable in the parent scope.

In _some_ cases I would like to use the same variable name to avoid having to come up with new names. Contrived example ahead:

```js
import path from "path"

function doSomething (_path) {
	if (path.dirname(_path) === "/" ) {
	// ...
 	} else {
	}
}
```

It would be nice if there was a special construct like `typeof` or `instanceof` that would take a name and evaluate to whatever 
variable / function of the same name existing in the parent scope (or undefined otherwise).

```js
import path from "path"

function doSomething (path) {
	if ((insteadof path).dirname(path) === "/" ) {
	// ...
 	} else {
	}
}
```

In this case the expression above using the made-up `inteadof` operator would evaluate to the imported `path` variable
instead of the `path` variable name.


Regards


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