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Re: need for macros (was Re: Icon)

Yes, Dan used to assign this as a puzzle in 1983/84 and I posed it to Guy
at my first POPL: it's called ONCE. You are creating a 3-dimensional value
that tunnels its way from expansion to run-time. Is this a good thing? 

If you read my message closely, you will see that I first used syntactic
abstraction and then in paren (macro). This is a fine distinction but an
important one. A mechanism for syntactic abstraction does just that: 

 abstract syntactic patterns. 

That's why I could come up with rules for when to use it and when not. 

Macros, on the other hand, have more power that syntactic abstractions. 
I am not sure I am willing to live with this. (That's why Schemer's call 
me an MLer, and MLer's call me a Schemer. Condemned by both :-) 

-- Matthias