lean4-htt

Lean 4 fork for HoTT-compatible kernel extensions (Path types, transport, HITs). Maintained against upstream leanprover/lean4.

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Leonardo de Moura a7d08d2f3d feat(kernel/inductive/inductive): dependent elimination for inductive predicates In Lean4, we will not generate non dependent recursors for inductive predicates. The main goal is to make the shape of the automatically generated recursors more uniform. The non uniform representation is leftover from Lean2. In Lean2, we wanted to support different kernels with different features. For example: we could create proof relevant kernels, no impredicative universe, etc. Recall that, in a kernel with an impredicative Prop and no proof irrelevance, inductive predicates without dependent elimination are weaker that inductive predicates with dependent elimination. When proof irrelevance is enabled, we can generate the dependent recursor from the non dependent one. Actually, the module drec.cpp generates the dependent recursor. Now, we only support one kind of kernel, and it doesn't make sense anymore to generate non dependent recursors for inductive predicates. This would only produce an unnecessary asymmetry on the inductive datatype module. Remark: we had to create non dependent recursors to help the elaborator. This can be avoid if we improve the elaborator. I will do that in the new elaborator implemented in Lean. Remark: equation lemmas are broken for definitions that pattern match on nested inductive datatypes. The problem is the super messy `prove_eq_rec_invertible_aux` function. This function will not be needed after I finish the new inductive datatype support in the kernel. cc @kha		2018-06-12 13:03:26 -07:00
.github	chore(.github/CONTRIBUTING): fix typos and URLs	2017-10-30 16:23:22 +01:00
bin	chore(bin/lean-gdb.py): fix lean::name pretty printer and add lean::obj_list pretty printer	2018-06-06 15:36:28 +02:00
doc	chore(script/prepare-commit-msg): remove file extension, guess change type	2018-06-12 17:39:59 +02:00
extras/latex	chore(extras/depgraph): remove leandeps	2017-07-15 02:27:17 -07:00
gen	chore(runtime): `lean_obj.` ==> `object.`	2018-05-20 10:17:15 -07:00
images	chore(CMakeLists.txt): move Lean logo to make sure we can test leanemacs without installing Lean	2015-01-31 17:38:49 -08:00
leanpkg	chore(leanpkg): delete	2018-04-10 12:43:17 -07:00
library	feat(kernel/inductive/inductive): dependent elimination for inductive predicates	2018-06-12 13:03:26 -07:00
old_tests/tests	feat(frontends/lean/definition_cmds): elaborate a def's type separately when explicit return type is given	2018-04-20 09:59:09 -07:00
packages	chore(script/test_registry): Replace with leanpkg. Execute in every artifact-producing build configuration.	2017-12-20 14:01:45 -08:00
script	chore(script/prepare-commit-msg): remove file extension, guess change type	2018-06-12 17:39:59 +02:00
src	feat(kernel/inductive/inductive): dependent elimination for inductive predicates	2018-06-12 13:03:26 -07:00
tests	chore(tests/lean/lisp): speed up test	2018-06-12 17:39:59 +02:00
tmp	chore(tmp/lean4.md): moved to google docs	2018-03-20 17:26:43 -07:00
.appveyor.yml	chore(.appveyor,.travis): disable leanpkg registry tests	2018-04-12 18:32:20 +02:00
.clang-format	feat(library/vm/process): add basic process support	2017-03-28 18:08:06 -07:00
.codecov.yml	fix(.codecov.yml): do not fail github ci if coverage drops by 0.01%	2017-06-25 10:35:02 +02:00
.gitattributes	chore(.gitattributes): use `union` merge strategy for doc/changes.md	2017-12-11 12:49:10 +01:00
.gitignore	chore(.gitignore): ignore `*.produced.out` files	2018-05-01 08:43:46 -07:00
.travis.yml	chore(.travis.yml): trigger AppVeyor nightly build from Travis	2018-04-13 16:44:27 +02:00
LICENSE	Add LICENSE file	2013-07-15 18:55:48 -07:00
README.md	chore(README): point CI links to lean4 branch	2018-04-12 13:50:42 +02:00