|Just happened to be reading one of the old (now outdated) Arc essays http://www.paulgraham.com/ilc03.html|
So, for example, it is not illegal in Arc to use the same variable twice in a parameter list. There's a consistent interpretation of such code-- bind the parameters left to right-- and that's what I do.
You know, I actually tried to do this once. I forget exactly what I was doing, but I had some code like
where f was a variable that could be one of several functions. All the functions needed to take three arguments since they were all called the same way, but one of the functions didn't use its first two arguments. So for that function I typed:
(f x y z)
MzScheme didn't like that of course. ^_^
(def foo (_ _ a)
Error: "lambda: duplicate argument name at: _ in: (lambda (_ _