code: public static LocalVariable uneraseGenericParameter(
              CodeBuilder b, TypeDesc paramType, final int paramIndex)
      {
          b.loadLocal(b.getParameter(paramIndex));
          b.checkCast(paramType);
          LocalVariable result = b.createLocalVariable(null, paramType);
          b.storeLocal(result);
          return result;
      }
docs: Generate code to create a local variable containing the specified parameter coerced
  to the specified type.  This is useful for re-interpreting erased generics into
  the more specific genericized type.
  
  @param b CodeBuilder into which to append the code
  @param paramType the more specific type which was erased during compilation
  @param paramIndex index of the parameter to unerase
  @return a local variable referencing the type-cast parameter