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Author SHA1 Message Date
Leonardo de Moura
305815cb56 feat(library/kernel_bindings): expose expr_binder_info in the Lua API 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-05-01 11:23:37 -07:00
Leonardo de Moura
97e7e4e762 test(lua): remove obsolete test 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-29 17:08:50 -07:00
Leonardo de Moura
fd034521dc feat(library/kernel_bindings): cleanup level Lua API 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-29 17:05:25 -07:00
Leonardo de Moura
93a61748e9 fix(kernel/level): bug in optional<level>() constructor 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-29 17:00:57 -07:00
Leonardo de Moura
984048f40d feat(library/kernel_bindings): new level Lua API 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-29 15:08:58 -07:00
Leonardo de Moura
a6116e3156 test(lua): reactivate some of the Lua unit tests 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-29 10:36:57 -07:00
Leonardo de Moura
e9dada5e14 refactor(builtin/kernel): use standard definition for 'or' and 'and' 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-17 12:05:34 -08:00
Leonardo de Moura
1739b5c153 fix(kernel/type_checker): caching bug 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-12 10:43:01 -08:00
Leonardo de Moura
368fcb5ff9 refactor(builtin/kernel): rename refute to by_contradiction 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-12 08:49:19 -08:00
Leonardo de Moura
b7b868de85 fix(library/elaborator): bug reported by Jeremy Avigad 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-10 14:01:22 -08:00
Leonardo de Moura
a2d2e36f04 refactor(frontends/lean): remove notation for creating tuples 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-10 09:03:42 -08:00
Leonardo de Moura
4317f67bd2 fix(builtin/tactic): more meaningful error message when skip tactic is used in a full proof 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-09 18:57:33 -08:00
Leonardo de Moura
c45c1748d8 refactor(builtin/kernel): reorder congr1 arguments 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-09 16:15:44 -08:00
Leonardo de Moura
8df7c7b02d feat(kernel/type_checker): remove fallback that expands opaque definitions in the type checker 
We should not rely on this feature. It can be quite expensive.
We invoke is_convertible in several places, in particular, if we are using overloading. For example, the frontend uses is_convertible to check which overload should be used. Thus, it will make several calls such as

   is_convertible(num, Nat)

If is_convertible starts unfolding opaque definitions, we would keep expanding num.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-09 11:31:24 -08:00
Leonardo de Moura
1ec01f5757 refactor(builtin): merge pair.lean with kernel.lean, and add basic theorems 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-07 16:04:44 -08:00
Leonardo de Moura
ad7b13104f feat(*): add support for heterogeneous equality in the parser, elaborator and simplifier, adjusts unit test to reflect changes 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-07 15:03:16 -08:00
Leonardo de Moura
d4b08fcf96 feat(library/elaborator): be 'lazy' when normalizing terms in the elaborator 
Unification constraints of the form

         ctx |- ?m[inst:i v] == T

         and

         ctx |- (?m a1 ... an) == T

are delayed by elaborator because the produce case-splits.
On the other hand, the step that puts terms is head-normal form is eagerly applied.
This is a bad idea for constraints like the two above. The elaborator will put T in head normal form
before executing process_meta_app and process_meta_inst. This is just wasted work, and creates
fully unfolded terms for solvers and provers.

The new test demonstrates the problem. In this test, we mark several terms as non-opaque.
Without this commit, the produced goal is a huge term.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-06 21:08:00 -08:00
Leonardo de Moura
593f1f2ebd fix(frontends/lean): allow user set constants defined in other namespaces as opaque 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-06 20:56:31 -08:00
Leonardo de Moura
363c4dc5c2 feat(library/elaborator): improve support for dependent pairs in the elaborator 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-06 20:56:31 -08:00
Leonardo de Moura
ea06bb2885 feat(frontends/lean/pp): change how lift local entries are pretty printed 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-06 17:26:38 -08:00
Leonardo de Moura
a51139e63b feat(frontends/lean): position information in error messages 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-06 17:26:38 -08:00
Leonardo de Moura
e4579b93e4 fix(library/elaborator): try first projection before imitation in the higher-order unifier 
Projections build more general solutions. This commit also adds a test that demonstrates the issue. Before this commit, the elaborator would produce the "constant" predicate (fun x, a + b = b + a).

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-06 13:35:05 -08:00
Leonardo de Moura
ef321e730f feat(builtin/tactic): add the 'skip' (bogus) tactic for ignoring a proof hole in a big proof 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-06 12:47:23 -08:00
Leonardo de Moura
eab0456b27 test(tests/lean): test super opaque style 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-06 11:33:27 -08:00
Leonardo de Moura
fdc4c9b53c test(tests/lean): add nested 'have' expression test 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-06 08:13:04 -08:00
Leonardo de Moura
1d23d93e60 feat(frontends/lean): new 'have' expression 
Add 'have' notation suggested by Jeremy Avigad.
Add his example to the test suite.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-06 08:03:59 -08:00
Leonardo de Moura
ba9a8f9d98 feat(frontends/lean): add 'show' expression syntax sugar 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-06 07:50:22 -08:00
Leonardo de Moura
419fb7464e fix(tests/lean): adjust tests to reflect recent changes 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-05 21:04:06 -08:00
Leonardo de Moura
aec9c84d0d fix(util/lua): deadlock 
Errors in the Lua library produce longjmps.
The longjmp will not unwind the C++ stack.
In the new test, the lock was not being released, and the system was deadlocking in the next call that tried to lock the environment

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-04 15:16:29 -08:00
Leonardo de Moura
f4ec874c6e refactor(builtin): remove dead module heq 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-04 14:42:28 -08:00
Leonardo de Moura
0283887ee9 refactor(builtin/kernel): move the heq axioms into kernel.lean 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-04 14:17:34 -08:00
Leonardo de Moura
f03c09c10b feat(library/elaborator): add support for proj/pair/sigma in the the higher-order unification procedure 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-04 13:53:30 -08:00
Leonardo de Moura
413391b2b4 chore(tests/lean/sig2): remove unnecessary parenthesis from test 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-04 11:37:08 -08:00
Leonardo de Moura
c9b72df34b fix(frontends/lean/parser): bug when applying tactics to synthesize remaining meta-variables 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-04 11:36:26 -08:00
Leonardo de Moura
96c9c7505a test(tests/lean): add another sigma-type test 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-04 10:12:39 -08:00
Leonardo de Moura
9dc86e3cf5 fix(builtin/kernel): rename generalized proof_irrel axiom to hproof_irrel, and derive the restricted one 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-04 10:06:29 -08:00
Leonardo de Moura
4fcc292332 feat(frontends/lean): parse and pretty print pair/tuple projection operators proj1 and proj2, fix bug in the type checker 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-03 22:10:01 -08:00
Leonardo de Moura
cc96b50644 feat(frontends/lean): support for nary-tuples, improve notation for non-dependent tuples, add support in the elaborator for sigma types 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-03 20:53:11 -08:00
Leonardo de Moura
5c991f8fbf feat(frontends/lean): parse and pretty print tuples/pairs 
This commit also fixes a bug in the type checker when processing dependent pairs.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-03 20:10:30 -08:00
Leonardo de Moura
640ebcc040 test(tests/lean/exp): add example for Steve 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-03 11:35:40 -08:00
Leonardo de Moura
e4afa3dc43 fix(tests/lean/map): incorrect output 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-03 00:05:19 -08:00
Leonardo de Moura
87f9c9b27e fix(tests/lean/map): make sure the unit test produce the same result in different platforms 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-02 20:29:34 -08:00
Leonardo de Moura
e2add5c9f2 test(tests/lean): add heterogeneous equality simplification example 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-02 20:27:39 -08:00
Leonardo de Moura
6be50f0133 refactor(builtin/heq): merge cast and heq modules 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-02 15:01:48 -08:00
Leonardo de Moura
c56df132b8 refactor(kernel): remove semantic attachments from the kernel 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-02 14:48:27 -08:00
Leonardo de Moura
2b7bc7b673 test(tests/lean/exp): simulating HOL constructions 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-31 17:59:57 -08:00
Leonardo de Moura
e3dc552c39 fix(library/simplifier): nontermination 
The example tests/lua/simp1.lua demonstrates the issue.
The higher-order matcher matches closed terms that are definitionally equal.
So, given a definition

    definition a := 1

it will match 'a' with '1' since they are definitionally equal.

Then, if we have a theorem

    theorem a_eq_1 : a = 1

as a rewrite rule, it was triggering the following infinite loop when simplifying the expression "a"

   a --> 1 --> 1 --> 1 ...

The first simplification is expected. The other ones are not.
The problem is that "1" is definitionally equal to "a", and they match.
The rewrite_rule_set manager accepts the rule a --> 1 since the left-hand-side does not occur in the right-hand-side.

To avoid this loop, we test if the new expression is not equal to the previous one.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-31 15:55:21 -08:00
Leonardo de Moura
1d85267d26 fix(library/simplifier): assumptions/context may contain equations where the left-hand-side is a metavariable or semantic attachment 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-31 15:38:22 -08:00
Leonardo de Moura
110ca84984 feat(library/simplifier): allow the user to associate a simplifier monitor with the lua_State object 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-31 13:49:24 -08:00
Leonardo de Moura
759aa61f70 refactor(builtin/kernel): define if-then-else using Hilbert's operator 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-30 19:28:42 -08:00
Leonardo de Moura
b45ab9dc30 feat(library/elaborator): use equality constraints instead of convertability constraints on definitions 
Convertability constraints are harder to solve than equality constraints, and it seems they don't buy us anything definitions. They are just increasing the search space for the elaborator.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-30 14:13:21 -08:00
Leonardo de Moura
8c1f6b9055 fix(kernel/typechecker): allow elaborator to infer (Type U+1) 
In the new test elab8.lean, the parameter B is in (Type U+1).
Before, this commit, the type checker was forcing all metavariables that must be types to be <= (Type U). This restriction was preventing the elaborator from succeeding in reasonable cases.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-30 14:00:01 -08:00
Leonardo de Moura
41f5e2a067 feat(library/simplifier): statically check (conditional) equations (aka rewrite rules) to verify whether we can skip type checking when using them in the simplifier 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-29 18:32:40 -08:00
Leonardo de Moura
01259b1e84 feat(kernel): make sure U is the maximal universe 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-29 16:31:00 -08:00
Leonardo de Moura
ea6bf224e5 feat(frontends/lean): make the parser accept (Type -> ...) 
Before this commit, the parser would accept only a universe level or a ')' after '(' 'Type'

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-29 15:23:20 -08:00
Leonardo de Moura
4f3127d3d5 fix(library/simplifier): check if the given types are convertible to ceq expected types 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-29 15:15:55 -08:00
Leonardo de Moura
0bb8fe75b3 test(tests/lean): new simplifier test 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-29 14:21:18 -08:00
Leonardo de Moura
a19f9d4846 feat(library/simplifier): discard conditional equations that are clearly non-terminating 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-29 13:56:45 -08:00
Leonardo de Moura
dd6aae378f fix(library/simplifier): must use metavar_env in is_ceq, otherwise it may ceqs that contain metavariables 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-29 13:29:20 -08:00
Leonardo de Moura
4dc3aa46c3 feat(frontends/lean): allow tactics to be used in axiom/variable declarations and in the type of definitions/theorems; add a new test showing the need for this feature 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-29 12:02:12 -08:00
Leonardo de Moura
069e5edf6b fix(library/simplifier): include flag indicating if the proof generated by simplifier is a homogenous or heterogenous equality, use flag to fix bug in the simp_tactic 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-29 12:01:01 -08:00
Leonardo de Moura
62408a6adc test(tests/lean): move simp_loop test to slow subdirectory 
This example produces a stackoverflow on Valgrind.
We don't execute Valgrind on tests in the slow subdirectory.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-29 10:32:48 -08:00
Leonardo de Moura
92ba4e8b2d feat(library/simplifier): add support for metavariables in conditional rewrite rules 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-29 08:34:04 -08:00
Leonardo de Moura
ee4344076e feat(library/simplifier): improve error message when simplifier is looping 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-28 19:36:31 -08:00
Leonardo de Moura
72c607846a test(tests/lean): add Jeremy's proof to test suite 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-28 16:05:46 -08:00
Leonardo de Moura
7f53cb9601 feat(frontends/lean/parser): add_rewrite take the 'using' command into account 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-28 01:15:28 -08:00
Leonardo de Moura
b31ef34787 feat(library/simplifier): preserve binder names when applying higher-order rewrite rules 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-28 00:50:27 -08:00
Leonardo de Moura
6da1b447f0 fix(library/hop_match): do not match iff with = 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-28 00:21:05 -08:00
Leonardo de Moura
db45d02078 fix(tests/lean): test discrepancy on OSX 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-27 23:31:35 -08:00
Leonardo de Moura
7b88d68afb test(tests/lean): add test using simplifier monitor for tracking failures 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-27 15:11:16 -08:00
Leonardo de Moura
8bccfb947a feat(library/simplifier): expose simplier and simplifier_monitor objects in the Lua API 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-27 15:02:05 -08:00
Leonardo de Moura
b26035fcf6 feat(kernel/type_checker): improve application type mismatch error messages 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-27 09:45:17 -08:00
Leonardo de Moura
4d25cb7f47 feat(library/tactic): add simplify_tactic based on the simplifier 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-26 18:53:18 -08:00
Leonardo de Moura
844572c382 feat(library/simplifier): support for dependent simplification in Pi/forall expressions 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-26 00:32:05 -08:00
Leonardo de Moura
e8bba1ebf3 fix(frontends/lean/frontend): the definition of the explicit version @f must be definitionally equal to f 
Before this commit, the explicit version @f of a constant f with implicit arguments as not definitionally equal to f.

For example, if we had

variable f {A : Type} : A -> Bool

Then, the definition of @f was

definition @f (A : Type) (a : A) : Bool := f A a

This definition is equivalent to
     fun A a, f A a
which is not definitionally equal to
     f
since definitionally equality in Lean ignores Eta conversion.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-25 20:34:28 -08:00
Leonardo de Moura
9fb3ccb4c0 feat(library/simplifier): support for dependent simplification in lambda expressions 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-25 16:54:42 -08:00
Leonardo de Moura
5b13ef1b90 test(tests/lean): new simplifier test 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-25 10:56:49 -08:00
Leonardo de Moura
7015089734 fix(library/simplifier): move to locally nameless approach in the simplifier. Contextual simplification may add rewriting rules with free variables, and it is a mess to manage them when using de Bruijn indices 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-25 10:49:44 -08:00
Leonardo de Moura
7a4eb4b8ed feat(library/simplifier): contextual simplification for A -> B 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-24 22:32:55 -08:00
Leonardo de Moura
c2381e43f1 fix(library/simplifier): bug in cast elimination 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-24 21:25:09 -08:00
Leonardo de Moura
35ad156a46 fix(tests/lean): make sure pretty print and parse test passes 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-24 17:23:55 -08:00
Leonardo de Moura
8f455f5965 fix(frontends/lean): bug in scope construct 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-24 17:23:29 -08:00
Leonardo de Moura
7f3e2b3ef4 fix(frontends/lean/parser): bug in 'using' construct 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-24 17:09:46 -08:00
Leonardo de Moura
8e0888828d fix(library/simplifier): missing check in mk_hcongr_th 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-24 17:09:46 -08:00
Leonardo de Moura
1a3660180e test(tests/lean): add new simplifier test 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-24 17:09:46 -08:00
Leonardo de Moura
26bea77721 fix(library/simplifier): bug in heterogeneous equality support, and universe commutativity support in the simplifier 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-24 17:09:46 -08:00
Leonardo de Moura
dbc100cc2e feat(library/simplifier): cast elimination in the simplifier 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-23 17:28:14 -08:00
Leonardo de Moura
cd87cb3de4 test(tests/lean): add test for congruence theorem that uses an argument before simplification 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-23 13:26:09 -08:00
Leonardo de Moura
180be5c4a2 feat(library/simplifier): improve contextual simplifications 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-23 13:11:58 -08:00
Leonardo de Moura
5ba2525eab test(tests/lean): add test disabling contextual simplifications 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-23 12:57:05 -08:00
Leonardo de Moura
33193e1ab3 feat(library/simplifier): improve contextual simplifications 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-23 12:54:29 -08:00
Leonardo de Moura
d6692264e8 feat(library/simplifier): contextual simplifications 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-23 12:23:22 -08:00
Leonardo de Moura
1638a7bb02 fix(frontends/lean/pp): compute local shared nodes, and avoid unnecessary let's 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-22 21:44:24 -08:00
Leonardo de Moura
17cce340f6 fix(library/elaborator): in optimization for metavariable free terms 
The optimization was incorrect if the term indirectly contained a metavariable.
It could happen if the term contained a free variable that was assigned in the context to a term containing a metavariable.

This commit also adds a new test that exposes the problem.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-22 18:06:00 -08:00
Leonardo de Moura
8214c7add4 feat(library/elaborator): compensate the lack of eta-reduction (and eta-expanded normal forms) in the kernel normalizer 
Before this commit, the elaborator was solving constraints of the form

       ctx |- (?m x) == (f x)
as
       ?m <- (fun x : A, f x)    where A is the domain of f.

In our kernel, the terms f and (fun x, f x) are not definitionally equal.
So, the solution above is not the only one. Another possible solution is

       ?m  <- f

Depending of the circumstances we want  ?m <- (fun x : A, f x) OR ?m <- f.
For example, when Lean is elaborating the eta-theorem in kernel.lean, the first solution should be used:
       ?m <- (fun x : A, f x)

When we are elaborating the axiom_of_choice theorem, we need to use the second one:
       ?m <- f

Of course, we can always provide the parameters explicitly and bypass the elaborator.
However, this goes against the idea that the elaborator can do mechanical steps for us.

This commit addresses this issue by creating a case-split
       ?m <- (fun x : A, f x)
       OR
       ?m <- f

Another solution is to implement eta-expanded normal forms in the Kernel.

With this change, we were able to cleanup the following "hacks" in kernel.lean:
     @eps_ax A (nonempty_ex_intro H) P w Hw
     @axiom_of_choice A B P H
where we had to explicitly provided the implicit arguments

This commit also improves the imitation step for Pi-terms that are actually arrows.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-22 13:28:54 -08:00
Leonardo de Moura
331b5846c6 test(library/simplifier): add test for the single_pass option in the simplifier 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-21 13:47:54 -08:00
Leonardo de Moura
ead54bbf57 feat(library/simplifier): enforce max_steps option 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-21 12:12:17 -08:00
Leonardo de Moura
1ccfac5873 feat(library/simplifier): conditional rewriting 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-20 21:15:46 -08:00
Leonardo de Moura
1ef75a9ba6 test(tests/lua): add test/example that demonstrates how to collect statistics of used theorems 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-20 18:04:22 -08:00
Leonardo de Moura
6bcd8e3ee5 fix(library/expr_lt): use expression depth instead of size to obtain a monotonic total order on terms 
It is not incorrect to use size, but it can easily overflow due to sharing.
The following script demonstrates the problem:

local f = Const("f")
local a = Const("a")
function mk_shared(d)
   if d == 0 then
      return a
   else
      local c = mk_shared(d-1)
      return f(c, c)
   end
end
print(mk_shared(33):size())

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-20 17:40:49 -08:00