Something I occasionally saw people do in lisp was (frob foo :quick (not :sneaky) :force) which could be done with strings in other languages foo.fro

Something I occasionally saw people do in lisp was (frob foo :quick (not :sneaky) :force) which could be done with strings in other languages foo.frob('quick', not 'sneaky', 'force') It's not ideal, because it makes it look like the arguments mean something. But if someone remembers that frob takes three boolean arguments, but doesn't remember what order they come in, this could be handy. Another option would be foo.frob(bool('quick'), not bool('sneaky'), bool('force')) but that's kind of verbose. EDIT: And the D approach posted above inspires this idea in python: class _ConstAttr: def __init__(self, const): self.const = const def __getattr__(self, attr): return self.const Yes = _ConstAttr(True) No = _ConstAttr(False) foo.frob(Yes.quick, No.sneaky, Yes.force) (It wouldn't be much use in Python, because of keyword arguments, but there might be languages without keyword arguments that could implement something like this. E.g. C macros YES(x) -> 1, NO(x) -> 0. It looks like D enforces the attribute name, so you can't get the arguments mixed up when writing and say No.sneaky, Yes.quick. It would be nice to get that as well.)