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Re: [Scheme-reports] auxiliary syntax



Alaric Snell-Pym scripsit:

> This, I think, is really just a matter of degree. As much as the bodies
> of let and cond deviate from normal scheme in that they contain lists
> whose first member is not a procedure to apply to something,

At the end of the day, that only works because the syntax expander has
hard-coded knowledge of lambda (and if).  It could also have hard-coded
knowledge of let, depending on whether the underlying Scheme is willing
to see lets or not.

> Alex wants to see symbols rather than identifiers. A macro is free to
> interpret cons cells, numbers, strings, and so on found in its body as
> it sees fit, so why can't it interpret symbols outside of the context
> of lexically bound identifiers?

It can, if it is not a syntax-rules macro; we all agree on that.
Forgive me for being thick, though; why isn't it enough to list these
symbols in the exceptions list of syntax-rules?  Isn't the whole point
of those that they match as if non-hygienic regardless of whether they
have been bound to a syntax error (as in R7RS) or not (as in R5RS)?

-- 
John Cowan    http://ccil.org/~cowan    cowan@x
The work of Henry James has always seemed divisible by a simple dynastic
arrangement into three reigns: James I, James II, and the Old Pretender.
                --Philip Guedalla

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