lean2/tests/lean/run/nat_bug7.lean

import logic

inductive nat : Type :=
zero : nat,
succ : nat → nat

namespace nat
definition add (x y : nat) : nat := nat.rec x (λn r, succ r) y
infixl `+` := add

axiom add_right_comm (n m k : nat) : n + m + k = n + k + m
open eq
print "==========================="
theorem bug (a b c d : nat) : a + b + c + d = a + c + b + d
:= subst (add_right_comm _ _ _) (eq.refl (a + b + c + d))
end nat
fix(library/unifier): bug that was making unifier miss solutions, and add a new case-split that tries to solve flex_rigid constraints by putting the rhs into whnf Signed-off-by: Leonardo de Moura <leonardo@microsoft.com> 2014-07-31 21:36:13 +00:00			`import logic`

			`inductive nat : Type :=`
feat(*): change inductive datatype syntax Signed-off-by: Leonardo de Moura <leonardo@microsoft.com> 2014-08-22 22:46:10 +00:00			`zero : nat,`
			`succ : nat → nat`
fix(library/unifier): bug that was making unifier miss solutions, and add a new case-split that tries to solve flex_rigid constraints by putting the rhs into whnf Signed-off-by: Leonardo de Moura <leonardo@microsoft.com> 2014-07-31 21:36:13 +00:00
feat(frontends/lean/inductive_cmd): prefix introduction rules with the name of the inductive datatype Signed-off-by: Leonardo de Moura <leonardo@microsoft.com> 2014-09-04 23:36:06 +00:00			`namespace nat`
refactor(kernel/inductive): replace recursor name, use '.rec' instead of '_rec' Signed-off-by: Leonardo de Moura <leonardo@microsoft.com> 2014-09-04 22:03:59 +00:00			`definition add (x y : nat) : nat := nat.rec x (λn r, succ r) y`
feat(frontends/lean): validate infixl/infixr/postfix/prefix declarations against reserved notations 2014-10-21 22:27:45 +00:00			infixl `+` := add
fix(library/unifier): bug that was making unifier miss solutions, and add a new case-split that tries to solve flex_rigid constraints by putting the rhs into whnf Signed-off-by: Leonardo de Moura <leonardo@microsoft.com> 2014-07-31 21:36:13 +00:00
			`axiom add_right_comm (n m k : nat) : n + m + k = n + k + m`
refactor(library): add 'eq' and 'ne' namespaces Signed-off-by: Leonardo de Moura <leonardo@microsoft.com> 2014-09-05 01:41:06 +00:00			`open eq`
fix(library/unifier): bug that was making unifier miss solutions, and add a new case-split that tries to solve flex_rigid constraints by putting the rhs into whnf Signed-off-by: Leonardo de Moura <leonardo@microsoft.com> 2014-07-31 21:36:13 +00:00			`print "==========================="`
			`theorem bug (a b c d : nat) : a + b + c + d = a + c + b + d`
feat(frontends/lean/inductive_cmd): prefix introduction rules with the name of the inductive datatype Signed-off-by: Leonardo de Moura <leonardo@microsoft.com> 2014-09-04 23:36:06 +00:00			`:= subst (add_right_comm _ _ _) (eq.refl (a + b + c + d))`
			`end nat`