Make visitors compatible with ppxlib 0.22.0
In ppxlib 0.22.0, the internal AST got bumped to ocaml 4.12. This commit adapts visitors to the compiler changes from 4.11 to 4.12: mainly, the introduction of injectivity to type declarations.
Prochaines maintenances programmées: lundi 06/05, lundi 03/06, lundi 01/07
Pour plus d'informations: https://doc-si.inria.fr/display/SU/Gitlab
In ppxlib 0.22.0, the internal AST got bumped to ocaml 4.12. This commit adapts visitors to the compiler changes from 4.11 to 4.12: mainly, the introduction of injectivity to type declarations.