Unused variables should produce a warning about coffeelint

[clutchski]

Already reported in issue #20, but you're definitely correct. Thanks for the feedback.

[juanique]

Can I still comment if the issue is closed?

I just want to point out hat issue #20 is about undefined variables, while this issue is about unused variables.

Example

myFunc = ->
    language = "coffee"
    checkWithLint = true

    return language

The variable checkWithLint is well defined, but is not used. Since the scope of the variable ends with the function definition, there is no way that the variable could be referenced from somewhere else, hence the assignment is unnecessary.

[swang]

I know this is an old ticket, so this may not get noticed. What should coffeelint spit out for this?

myFunc = ->
   useThis = "useThis"
   useThat = "useThat"
   if Math.floor(Math.random()*100) % 2 is 0
      useThat
   else
      useThis

Should it not give any warnings/errors because all variables are mentioned somewhere in the function?

Also should functions be ignored? What about functions in 'global' space (like functions you would define in a module)?

[AsaAyers]

The warning about undefined variables has not been implemented. I attempted it, but ran into complications with destructuring assignments.

If it were implemented it should not warn about that code.

[joelbarker2011]

Not sure why this issue was closed; it is definitely (still) a problem.

[AsaAyers]

It's closed because it's not going to get implemented. See #20 (comment)

I also recommend reading my post: You Don't Need CoffeeScript