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Re: Prefix, not postfix (poll)




On Tue, 11 Apr 2006, Eli Barzilay wrote:

>On Apr 11, Ben Goetter wrote:
>> [...]
>> Syntax-rules should treat keywords as valid /identifier/s in a
>> production.  I am thinking of the ":" token in Scsh SRE syntax.
>
>Why?  Keywords are a new type, so they should be used as valid
>identifiers in syntax just like numbers, strings, and booleans.

Here's the thing; I don't think keywords express anything that
isn't expressed by an existing type.  Their value is in the
gray area of *limiting* what you can do with some set of symbols.
And the philosophical arguments around that are kinda murky -
especially in a language like scheme, which demonstrates
the power of *removing* such arbitrary limitations wherever
possible.

If we think that a variable being immutably bound to a
particular value, and un-shadowable with a variable of the
same name and different binding, is a good idea, then we
should be talking about the new ideas generally - immutable,
global and unshadowable bindings - not about a particular
application of them as keywords.

					Bear