# File lib/method_source/source_location.rb, line 40
        def source_location
          if @file.nil?
            args =[*(1..(arity<-1 ? -arity-1 : arity ))]

            set_trace_func method(:trace_func).to_proc
            call(*args) rescue nil
            set_trace_func nil
            @file = File.expand_path(@file) if @file && File.exist?(File.expand_path(@file))
          end
          return [@file, @line] if File.exist?(@file.to_s)
        end