docs: document canonical order in toposort for nodes of the same rank#280
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aborgna-q merged 2 commits intoQuantinuum:mainfrom Feb 25, 2026
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toposort for nodes of the same ranktoposort for nodes of the same rank
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Kahn's algorithm alone does not provide a canonical order for nodes of the same rank. The order depends on the data structure used to store "discovered" nodes that haven't been visited yet.
I've clarified this in the docs for
toposort,toposort_filteredandToposort, adding that we use a queue to determine the order within the same rank, resulting in ties being broken by visiting nodes in the same order they are discovered. I also updated the example given fortoposortto exhibit this tie-breaking behavior.All tests pass.