Closed subttle closed 4 years ago
Looks like Antimirov's AX axioms [1] [2] might be be preferable for extended regular expressions: [1] Manipulation of Extended Regular Expressions with Derivatives, Rafaela Carolina Ribeiro Bastos http://www.dcc.fc.up.pt/~nam/web/resources/rafaelamsc.pdf [2] Rewriting Extended Regular Expressions, Valentin M. Antimirov, Peter D. Moses https://hope.simons-rock.edu/~pshields/cs/cmpt320/antimirov94.pdf
This should come in handy when switching axioms :)
Kozen axioms for Kleene Algebra in Agda https://github.com/subttle/kleene
For now what I've convinced myself I want is Kozen axioms [1] for RE and Salomaa axioms [2] for ERE.
[1] A Completeness Theorem for Kleene Algebras and the Algebra of Regular Events, Dexter Kozen https://www.cs.cornell.edu/~kozen/Papers/ka.pdf
[2] Two Complete Axiom Systems for the Extended Language of Regular Expressions, Salomaa and Tixier (01687431.pdf) Available free through https://ieeexplore.ieee.org/Xplore/home.jsp ("IEEE Transactions on Computers" C-17) with some school proxies.