Allow variable shadowing (re-declaration)

[jshint]

Allow variable shadowing (re-declaration)

[devinus]

This is easy. All you have to do is drop the var:

function test(foo) {
    foo = foo || false;
}

I seriously don't think this needs to be looked at.

[davebalmer]

Sure, it looks like a simple solution in this 2 line example, but there's actually nothing wrong with using var in this case. I see no reason why this checking can't be turned off, especially when JSure supports this option.

I'm pretty sure we don't want to make another jslint. :)

[valueof]

Why did you close the issue? Since re-declaring variables does not break any code, I don't see why can't we make it an option.

[devinus]

Oops, who closed it? I certainly didn't mean to if it was me, those damn buttons are too close to each other. I apologize if it was me.

[GarrettS]

I agrtee with devinus about the buttons I've almost clicked that "comment and close " myself. Odd, I only see "comment" now.

And about redeclaring, I also agree that it's better to omit var.

The warning helps because redeclaring a variable is usually a mistake. The one good reason I can think of for wanting to redeclare a variable is only for global scope. The case I am thinking of is where the identifier is declared and may be conditionally assigned but the declaration happens inside the if's block. But I think there is already a separate issue for that.

if(typeof Hammer != "object") {
  var Hammer = {};
}

[davebalmer]

I can't think of a case where I accidentally re-declared a variable. In any case, I don't see where having the option to turn this off is a bad thing. Make it default to "on", that's fine.

And yes, your global case is a very valid yet different use case, and probably shouldn't be lumped in with this one.

While we're on it, I have cases where I look for console and if it doesn't exist, I add a stubbed out console.log(). This isn't an uncommon practice, especially with code that's in development or with internal tools. Right now, it throws an "attempted to replace read-only" error.

While we're on that tangent, one nice feature with JSure is you can set error checking flags to "off", "error" or "warn". The significance of that really shows up when you use a tool like this in an automated build environment, where throwing an error will stop the build, rather than just alert the developer that there may be a problem.

Oh, and I may have accidentally closed this myself. Those buttons are way to close; I just caught my mouse hovering over "Comment and Close". :)

[neonstalwart]

is this issue a duplicate of #14

[davebalmer]

Similar, but not a duplicate. At least, seems to throw a different error.

[valueof]

Implemented in master as an opt-in shadow option.