Imported From: https://issues.scala-lang.org/browse/SI-8040?orig=1
Reporter: @sschaef
Affected Versions: 2.11.0
See #7707, #9158, #9518, #7712

@paulp said:
I initially did that, then backed off in terror from the hundreds if not thousands of warnings the compiler emitted. The prevailing style inside the compiler involves a lot of pattern matches like this:

      case ValDef(mods, name, tpt, rhs) =>
        ctx // we use the symbol to add fields
      case DefDef(mods, name, tparams, vparamss, tpt, rhs) =>
        // let's do nothing!

That's ten unused warnings, now multiply by one billion. Maybe this problem is unique to the compiler.

@som-snytt said (edited on Aug 19, 2016 6:42:06 PM UTC):
There are a few specific examples for improving unused warning.

Another request: unused parameters, especially implicits, and also when shadowed by locals.

Don't warn if param is mandated by superclass API, or if param is deprecated.

@som-snytt said:
scala/scala#5402