Some extra support for homogeneous n-ary products #2736
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JacquesCarette
approved these changes
Jun 19, 2025
MatthewDaggitt
commented
Jun 21, 2025
Co-authored-by: jamesmckinna <[email protected]>
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Lately my students and I have been writing a lot of code with N-ary products where all elements either belong to types with the same universe level or belong to the same types. This adds some extra infrastructure to make this all a little bit nicer.
If
⨆(which acts as a fold) took a level for then = zerocase instead of defaulting toLevel.zerothen we could prove thatHomoProduct n A : Set ainstead ofHomoProduct n A : Set (lconst n a). However, a) that is a breaking change and b) there's no nice way that I can see to make that cast so that the other n-ary functions over n-ary products can see through the cast. Therefore leaving as is in order to make incremental progress