[plt-scheme] Help With Reduction Semantics?

From: Robby Findler (robby at cs.uchicago.edu)
Date: Tue Aug 17 22:15:21 EDT 2004

At Tue, 17 Aug 2004 19:09:16 -0700, Paul Snively wrote:
> Ontic allows the infinite set of quoted symbols in the grammar. How
> would I express that?

You can write this:

    (syms 'variable))

or if you want to omit a few keywords, you write this:

    (syms '(variable-except x y z quote)))

This plays on the same pun that Scheme itself does -- a symbol is just
a variable with a ' in front of it. In fact, the above is exactly the
same as:

    (syms (quote variable)))

The tick mark is just a shorthand notation.


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