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>> 3. The new stuff can have completely different parsing rules to
>> Haskell. (Presumably the Lisp, Forth and Erlang methods can't do that.)
>
> Erlang, no, because it's already parsed when you get it. FORTH and LISP,
> yes, it's exactly the point of it. If you can read arbitrary amount of
> input off the input file as you're compiling, you can pretty much
> completely change the parsing rules.
The way you said "take each token and pass it through a macro" made it
sound like the input stream gets tokenised first - which means if what
you want to quote has different ideas about what constitutes a "token",
you've got a problem.
>> If you could write XML tags literally, then an expression like "if x<y
>> then if y>z then..." would suddenly parse as an XML tag, which would
>> be a Very Bad Thing. Really, having to explicitly say you're doing
>> weird stuff isn't so bad.
>
> Yeah, that was just an example I saw. Obviously you'd have to take care.
> I haven't used Erlang enough to understand the subtleties of its
> mechanisms.
Square enuf.
--
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