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Re: sxml-match bad pattern syntax


From: Thien-Thi Nguyen
Subject: Re: sxml-match bad pattern syntax
Date: Tue, 28 Dec 2021 04:21:39 -0500
User-agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux)

() <tomas@tuxteam.de>
() Tue, 28 Dec 2021 09:28:32 +0100

   > Ah, right!  The ellipses are a tail that need to follow a
   > head.

   No, the ellipses tell the matcher that the symbol to its left
   acutally stands for "zero or more of this". Consequently, you
   have to somehow [1] use those ellipses on the right hand side
   (aka template) whenever you use them on the left hand side
   (aka pattern) and vice versa.

I think we're saying the same thing, but in any case, i
understand what you're saying.

   > I guess i was confused by the documentation's use of
   > ellipses in the conventional sense rather than the literal
   > sense:

   I think of the ellipses as a kind of funny Kleene star. Not
   really at home in any world: in the regular world, because it
   isn't a star, in the Scheme world, because it is postfix.

That's a really good analogy, IMHO.  It's an operator of sorts.

   [examples]

Yes, it's becoming more clear to me now.

   For the idiomatic part, I'll have to defer to those with more
   chevrons ;-)

:-D

I think the ‘otherwise’ clause is a bit unwieldy; it presumes
normal form 3 (attribute lists always present).  However, i
couldn't find a way to match "any element".  ISTM the element
portion (first symbol in the form) MUST be non-variable.

-- 
Thien-Thi Nguyen -----------------------------------------------
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     (`(technical ,ml) (correctp ml))
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