This feels like an ideal use case for XSLT for-each-group—something that is challenging to implement in XQuery.
Cheers, E. _____________________________________________ Eliot Kimber Sr Staff Content Engineer Digital Content & Design O: 512 554 9368 M: 512 554 9368 servicenow.com<https://www.servicenow.com> LinkedIn<https://www.linkedin.com/company/servicenow> | Twitter<https://twitter.com/servicenow> | YouTube<https://www.youtube.com/user/servicenowinc> | Facebook<https://www.facebook.com/servicenow> From: BaseX-Talk <basex-talk-boun...@mailman.uni-konstanz.de> on behalf of Graydon Saunders <graydon...@gmail.com> Date: Thursday, March 28, 2024 at 7:43 AM To: BaseX <BaseX-Talk@mailman.uni-konstanz.de> Subject: [basex-talk] hof:until is gone? [External Email] ________________________________ Hello -- So I'm trying to do this: import module namespace xcs = "http://www.xcential.com/xquery/utils/script<http://www.xcential.com/xquery/utils/script>" at "same-words-same-order-script.xqm"; (: we don't need xc computationally but there are external variables in that namespace in scope :) import module namespace xc = "http://www.xcential.com/xquery/utils<http://www.xcential.com/xquery/utils>" at 'same-words-same-order.xqm'; declare function xc:dropTableLines($in as node()*,$toggle as xs:boolean) as node()* { switch (true()) case empty($in) return () case starts-with(head($in),':stab') return (<line/>,xc:dropTableLines(tail($in),true())) case starts-with(head($in),':rtab') return (<line/>,xc:dropTableLines(tail($in),false())) case $toggle return (<line/>,xc:dropTableLines(tail($in),$toggle)) default return (head($in),xc:dropTableLines(tail($in),$toggle)) }; let $test as element() := <text> <line></line> <line></line> <line>:stab</line> <line>weasels</line> <line>:stab</line> <line>weasels</line> <line></line> <line></line> <line>:rtab.</line> <line></line> <line>asparagus</line> <line></line> <line></line> <line>:stab</line> <line></line> <line>weasels</line> <line>:rtab.</line> <line>asparagus</line> <line>asparagus</line> <line>asparagus</line> <line>asparagus</line> <line>asparagus</line> <line>:stab</line> <line>:stab</line> <line></line> <line></line> <line>:stab</line> <line></line> <line>weasels</line> <line></line> <line>:rtab.</line> <line></line> <line>asparagus</line> <line></line> <line></line> <line></line> </text> return element {'text'} { xc:dropTableLines($test/line,false()) } Only at scale the stack blows up and I get the "try tail recursion?" suggestion. I would have tried hof:until for that, since I have to pass the current state of "are we dropping or not dropping intervening content?", but it looks like it's been removed? And the available hof functions in 4 look like they're strictly positional which is actively unhelpful in this case. (At least with whatever brain cells I currently have.) What's the appropriate pattern for "process a sequence, toggling an action on or off based on the last member of the sequence we looked at?" Thanks! Graydon