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A comment on Xee: A Modern XPath and XSLT Engine in Rust. Parent comment

Re:Xee: A Modern XPath and XSLT Engine in Rust by shawn_w on Friday March 28, 2025 @04:44PM (#43509655)
There's no ambiguity. The first element is a symbol that's the name of a tag. If the second element is a list of two element symbol + string lists, it's the attributes. If it's one of the other recognized types, it's part of the contents of the tag.

See a grammar for the representation at https://docs.racket-lang.org/xml/index.html#%28def._%28%28li...

Most Scheme tools for working with XML use a different layout where a list starting with the symbol @ indicates attributes. See https://en.wikipedia.org/wiki/SXML for it.

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Re:Xee: A Modern XPath and XSLT Engine in Rust by zoogeny on Saturday March 29, 2025 @01:54PM (#43517259)
I see, so my example should be:

    (foo (bar "baz") "content")
vs

    (foo ((bar "baz")) "content")
Where the first one would be the nested tags and the second one would be a single `bar="baz"` attribute.

I would prefer the differentiation to be more explicit than the position and/or structure of the list, so the @ symbol modifier for the attribute list in other tools makes sense.

The sibling comment with a map with a :attrs key feels even better. I don't work in languages with pattern matching or that kind of thing very often, but if I was wanting to know if a particular element had 1 or more attributes then being able to check a dictionary key just feels like a nicer kind of anchor point to match against.

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