Basic Order Theory #1154
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Basic Order Theory #1154
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Rename preorder to proset; rename strict poset to quoset (quasiorder) and add strict orders as quasiorders with weak linearity
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Note that while this is not immediately related to #1181, it does help set up some additional foundational stuff for orderings in general, such as basic definitions of lattices and meets/joins. |
felixwellen
approved these changes
Feb 7, 2025
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Introduces basic order theory (basics of lattices, downsets, upsets, poset closures; defines galois connections as well). Also cleans up a couple of order-related files for naturals and rationals and adds some useful lemmas to some algebra structures for use later. Renames and cleans up the various orderings as well. Also proves that embeddings form a complete lattice. Defines preimages as well.