Lean 4 fork for HoTT-compatible kernel extensions (Path types, transport, HITs). Maintained against upstream leanprover/lean4.
e6a07ca6b1
This PR cleans up the API around `String.find` and moves it uniformly to the new position types `String.ValidPos` and `String.Slice.Pos` Overview: - To search for a character, character predicate, string or slice in a string or slice `s`, use `s.find?` or `s.find`. - To do the same, but starting at a position `p` of a string or slice, use `p.find?` or `p.find`. - To do the same but between two positions `p` and `q`, construct the slice from `p` to `q` and then use `find?` or `find` on that. - To search backwards, all of the above applies, except that the function is called `revFind?`, there is no non-question-mark version (use `getD` if there is a sane default return value in your specific application), and that you can only search for characters and character predicates, not strings or slices. |
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| stage0 | ||
| tests | ||
| .gitattributes | ||
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| .ignore | ||
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| CODEOWNERS | ||
| CONTRIBUTING.md | ||
| flake.lock | ||
| flake.nix | ||
| lean-toolchain | ||
| lean.code-workspace | ||
| LICENSE | ||
| LICENSES | ||
| README.md | ||
| RELEASES.md | ||
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