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Category Errors

Danny says:

``We have NOT laid out the range of legal arguments for generic functions.''

My comment was:

``We've carefully laid out, in most cases, the range of legal arguments to
functions and generic functions in CLOS....''

I guess I shouldn't rely on subtle wording to get across a subtle point.
Here is a generic function ``in CLOS'':

	Add-method generic-function method

And here is how we have ``carefully laid out ... the range of legal
arguments'' to it:


	The generic-function argument is a generic function

	The method argument is a method object.  The
	lambda-list of the method function must be
	congruent with the lambda-lists of any other
	methods associated with the generic function and
	with the lambda-list of the generic function.

		(page 2-5, FUNCTIONS)

The thing in CLOS that is already the same sort of ``blemish'' as this
category error is discrimination on individuals. Blemish, beauty mark:
At least we can agree that in both cases an observer is justified in
thinking ``what's that thing?''