Add an enabledp check in deflogger at compile-time
Add an enabledp check in deflogger at compile-time

This means that when a logger is defined with a given level then
the messages below this level will be expanded to nil at compile time,
so they'll have no performance penalties at runtime.

An example setup:
  (deflogger foo :level +debug+) ; +debug+ level at compile-time
  (setf (log.level 'foo) +info+) ; set runtime level to +info+
  (foo.dribble "foo: ~S" (some-expensive-calculation)) ; expands to nil
  (foo.debug ...) ; will log if the runtime level is appropiate
nixeagle/cl-walker