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Author SHA1 Message Date
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
6cb4d165c9 feat(builtin/kernel): dependent version of axiom of choice 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-22 11:04:27 -08:00
Leonardo de Moura
88b6778a1f fix(emacs): syntax highlight 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-22 09:44:12 -08:00
Leonardo de Moura
66553268d0 feat(builtin/kernel): add skolem_th, we need it to justify skolemization preprocessing step 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-22 09:41:07 -08:00
Leonardo de Moura
d9b5ebc738 refactor(builtin/kernel): cleanup Hilbert operator definition 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-22 09:18:40 -08:00
Leonardo de Moura
bcf60db23b fix(builtin/kernel): Hilbert operator only for non-empty types 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-22 08:52:31 -08:00
Leonardo de Moura
94a3136904 feat(builtin/kernel): add Hilbert's operator, and derive axiom of choice using it 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-22 08:21:11 -08:00
Leonardo de Moura
425d31f513 chore(library/simplifier): fix style warning 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-21 21:45:55 -08:00
Leonardo de Moura
cca15f1390 feat(library/simplifier): congruence theorem compilation 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-21 21:16:23 -08:00
Leonardo de Moura
029d74ec11 chore(kernel): remove comment, we decided to have Eta as a simplification rule 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-21 14:35:05 -08:00
Leonardo de Moura
95b6e61738 feat(kernel/max_sharing): check for imminent stack overflows and interruptions in the expression sharing maximizer 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-21 14:33:49 -08:00
Leonardo de Moura
2089b85532 refactor(kernel/instantiate): remove code duplication 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-21 14:30:38 -08:00
Leonardo de Moura
7299b2d5d6 chore(kernel): remove dead file 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-21 14:21:13 -08:00
Leonardo de Moura
fbaf6e887f refactor(builtin/kernel): put the congruence theorems in a format that is easier for the simplifier to process 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-21 14:03:51 -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
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
Leonardo de Moura
cd19d4da01 feat(library/simplifier): memoize intermediate results 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-20 17:03:44 -08:00
Leonardo de Moura
97ead50a3e feat(builtin/Nat): flip orientation of associativity axioms for + and * 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-20 15:38:00 -08:00
Leonardo de Moura
ad219d43d9 refactor(*): semantic attachment parsing and simplification 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-20 14:44:45 -08:00
Leonardo de Moura
217e56ea03 feat(kernel/expr): make sure semantic attachments are smaller than other kinds of expression 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-20 14:10:44 -08:00
Leonardo de Moura
abfeacb8f0 fix(tests/library/expr_lt): adjust is_lt unit tests to reflect recent modifications 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-20 13:44:44 -08:00
Leonardo de Moura
56f5657ee7 fix(library/simplifier): ordered rewriting 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-20 13:13:16 -08:00
Leonardo de Moura
5060bdbf14 fix(kernel/expr): compilation warning 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-20 13:12:49 -08:00
Leonardo de Moura
6a63ef3bc5 feat(library/expr_lt): make sure the total order on terms is monotonic 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-20 13:07:18 -08:00
Leonardo de Moura
ac9f8f340d feat(kernel/expr): add efficient get_size() function for expressions 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-20 12:28:37 -08:00
Leonardo de Moura
913d893204 feat(library/simplifier): add support for 'permutation' rewrite rules 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-20 08:29:31 -08:00
Leonardo de Moura
8e90d17a0b fix(library/hop_match): style 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-19 23:28:12 -08:00
Leonardo de Moura
69d7ee316f feat(library/simplifier): improve simplification by evaluation 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-19 23:26:34 -08:00
Leonardo de Moura
08053c1172 feat(library/hop_match): make the higher order pattern matcher slightly stronger 
It now can handle (?m t) where t is not a locally bound variable, but ?m and all free variables in t are assigned.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-19 20:35:50 -08:00
Leonardo de Moura
90ffb9d5ec fix(frontends/lean/pp): bug in pp_abstraction_core 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-19 19:47:40 -08:00
Leonardo de Moura
6db10c577b feat(builtin/kernel): add proof irrelevance axiom 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-19 12:20:09 -08:00
Leonardo de Moura
d322f63113 feat(frontends/lea): add commands for creating and managing rewrite rule sets 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-19 12:03:59 -08:00
Leonardo de Moura
bbf6e6a256 feat(builtin/kernel): create default rule set in the kernel, and adjust unit tests 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-19 11:24:20 -08:00
Leonardo de Moura
3bbadddc94 chore(library/simplifier): cleanup and add comments 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-19 10:54:09 -08:00
Leonardo de Moura
7492fd5a2c feat(library/simplifier): add support for simplification by evaluation 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-19 10:34:55 -08:00
Leonardo de Moura
475df3d94e chore(builtin/kernel): add theorem for rewriter/simplifier 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-19 10:34:18 -08:00
Leonardo de Moura
e512241c8f fix(emacs): missing keyword 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-19 10:32:45 -08:00
Leonardo de Moura
11719713ec feat(library/hop_match): optionally unfold constants when performing higher order matching 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-19 10:32:06 -08:00
Leonardo de Moura
39c3b17eb7 feat(library/simplifier): add support for Eta-reduction in the simplifier 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-19 00:40:35 -08:00
Leonardo de Moura
ed009f4c88 feat(kernel/simplifier): add support for Beta-reduction in the simplifier 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-19 00:40:20 -08:00
Leonardo de Moura
7a3aab60c6 chore(builtin/kernel): remove \bowtie as notation for transitivity 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-18 21:11:12 -08:00
Leonardo de Moura
2753a0ffc0 fix(builtin/kernel): add ascii notation for transitivity 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-18 20:56:35 -08:00
Leonardo de Moura
32c5bc25e3 refactor(library/simplifier): cleanup rewrite_rule_set, and use it in the simplifier 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-18 20:52:33 -08:00
Leonardo de Moura
466285c577 refactor(library/simplifier): rewriter_rule_set 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-18 17:26:01 -08:00
Leonardo de Moura
feea96e84d feat(library/simplifier): add rewrite_rule_set extension for managing rewrite rules in an environment 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-18 15:43:24 -08:00
Leonardo de Moura
eae79877ae feat(library/simplifier): add rewrite_rule_set 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-18 12:50:46 -08:00
Leonardo de Moura
27ab49ae9d feat(library/simplifier): bottom-up simplifier skeleton 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-18 12:49:41 -08:00
Leonardo de Moura
40b7ed13c2 fix(tests/lean): adjust tests 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-17 19:27:32 -08:00
Leonardo de Moura
534838a36c chore(build): update automatically generated files 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-17 18:30:45 -08:00
Leonardo de Moura
d711ca4d1b feat(builtin/heq): add heq C++/Lean interface 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-17 18:30:21 -08:00
Leonardo de Moura
20c8b91d07 feat(builtin/if_then_else): add more theorems for rewriting 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-17 18:11:23 -08:00
Leonardo de Moura
2434024272 fix(library/rewriter): warning in release mode 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-17 15:46:49 -08:00
Leonardo de Moura
ba88a3b05a chore(builtin/heq): remove unnecessary import 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-17 15:40:56 -08:00
Leonardo de Moura
70828af6db refactor(builtin/heq): cleanup universes 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-17 14:52:09 -08:00
Leonardo de Moura
fc4c6454a7 chore(tests/lean): adjust tests to reflect recent changes 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-17 14:36:55 -08:00
Leonardo de Moura
0660cdbdb7 feat(builtin/cast): use heq in the cast library 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-17 14:31:45 -08:00
Leonardo de Moura
52756c50fc fix(builtin/heq): extensionality axioms 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-17 12:56:36 -08:00
Leonardo de Moura
64795c6c42 feat(builtin): add heterogeneous equality theory 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-17 12:32:49 -08:00
Leonardo de Moura
baed98d5be chore(builtin/kernel): adjust emacs mode and fix typo 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-17 10:14:57 -08:00
Leonardo de Moura
5bee259a00 refactor(kernel): remove unnecessary universe 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-16 18:06:25 -08:00
Leonardo de Moura
a43020b31b refactor(kernel): remove heterogeneous equality 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-16 17:39:12 -08:00
Leonardo de Moura
1da4294793 refactor(builtin): more theorems, fix iff notation 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-16 09:26:50 -08:00
Leonardo de Moura
398d83b6d5 chore(builtin/Nat): use iff 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-16 02:06:53 -08:00
Leonardo de Moura
4dc98bc73b refactor(builtin/kernel): use iff instead of = for Booleans 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-16 02:05:09 -08:00
Leonardo de Moura
d063828ff9 feat(library/kernel_bindings): expose abst_name, abst_domain and abst_body in the Lua API 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-16 00:03:16 -08:00
Leonardo de Moura
8d73fb5699 fix(library/hop_match): Lua bindings gotcha 
See http://www.luafaq.org/gotchas.html#T6.4

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-15 23:51:26 -08:00
Leonardo de Moura
14c6218bdc chore(kernel): file name convention 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-15 20:06:29 -08:00
Leonardo de Moura
3238c7e2a0 feat(library/simplifier): add is_permutation_ceq predicate 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-15 19:53:52 -08:00
Leonardo de Moura
7fb0aa4800 chore(kernel/expr): remove dead code 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-15 17:24:31 -08:00
Leonardo de Moura
438fa8251b test(kernel/expr): check if the serializer works for metavariables 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-15 17:15:56 -08:00
Leonardo de Moura
5058e403b5 test(kernel/expr): check if the serializer works for applications with many argumets 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-15 17:09:46 -08:00
Leonardo de Moura
c096eec1d6 chore(kernel/expr): remove dead code 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-15 17:09:04 -08:00
Leonardo de Moura
8c2f78a756 feat(builtin): minimize use of heterogenous equality in the kernel, add simpler version of congruence theorems for non-dependent types 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-15 16:34:23 -08:00
Leonardo de Moura
c73398a0b8 refactor(library/simplifier): relax rule for conditional equalities 
The idea is to support conditional equations where the left-hand-side does not contain all theorem arguments, but the missing arguments can be inferred using type inference.
For example, we will be able to have the eta theorem as rewrite rule:

theorem eta {A : TypeU} {B : A → TypeU} (f : ∀ x : A, B x) : (λ x : A, f x) = f
:= funext (λ x : A, refl (f x))

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-15 16:06:00 -08:00
Leonardo de Moura
3daac17ea8 feat(library/simplifier): convert disequalities (a ≠ b) into equations '(a = b) = false' 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-15 15:30:16 -08:00
Leonardo de Moura
1176093afa refactor(library/simplifier): simplifier should only use homogeneous equalities 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-15 14:58:32 -08:00
Leonardo de Moura
f177c8d1ec fix(library/elaborator): missing condition 
The elaborator was failing in the following higher-order constraint

   ctx |- (?M a) = (?M b)

This constraint has solution, but the missing condition was making the elaborator to reduce this problem to

   ctx |- a = b

That does not have a solution.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-15 14:11:36 -08:00
Leonardo de Moura
c651d3ea2d feat(library/simplifier): filter out propositions that cannot be used as conditional equations 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-15 12:06:27 -08:00
Leonardo de Moura
94fa987814 fix(kernel/type_checker): is_proposition method was still assuming that a Pi never has type Bool 
The method is_proposition was using an optimization that became incorrect after  we identified Pi and forall.
It was assuming that any Pi expression is not a proposition.
This is not true anymore. Now, (Pi x : A, B) is a proposition if B is a proposition.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-15 11:02:52 -08:00
Leonardo de Moura
3ab2d2a441 fix(frontends/lean/parser): memory leak due to g++ bug 
g++ implementation of std::initializer_list has bug.
http://gcc.gnu.org/ml/gcc-bugs/2013-06/msg00095.html

This commit memory leaks triggered by this bug.
It also adds minimal tests to expose three different instances of the problem.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-15 10:15:04 -08:00
Leonardo de Moura
83efa644d1 fix(frontends/lean/parser): uninitialized var error reported by valgrind 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-15 08:43:43 -08:00
Leonardo de Moura
28eb980484 fix(build): C++ module dependency problem, and style 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-14 18:30:31 -08:00
Leonardo de Moura
c8e1ec87d2 feat(library/simplifier): add to_ceqs function that converts a theorem into a sequence of conditional equations 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-14 18:30:19 -08:00
Leonardo de Moura
7c2a4211a8 feat(kernel): expose imported predicate 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-14 16:41:40 -08:00
Leonardo de Moura
07059b0531 feat(library): add if_then_else Lean/C++ interface 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-14 16:10:49 -08:00
Leonardo de Moura
8217a544cc fix(library/hop_match): bugs in the higher-order matching procedure, add more tests 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-14 14:37:28 -08:00
Leonardo de Moura
acfb11e290 fix(kernel/instantiate): relax apply_beta pre-condition 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-14 14:36:51 -08:00
Leonardo de Moura
a968a43487 fix(kernel/free_vars): make sure has_free_var does not return incorrect result due to arithmetic overflows 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-14 14:36:14 -08:00
Leonardo de Moura
f8eaae7218 feat(builtin/kernel): add new useful theorems for the simplifier 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-13 18:21:22 -08:00
Leonardo de Moura
4595c50f7e fix(library/hop_match): in locally bound variable management 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-13 18:06:23 -08:00
Leonardo de Moura
ccb9faf065 refactor(*): error messages 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-13 16:54:21 -08:00
Leonardo de Moura
55aa4cbfa3 feat(frontends/lean): improve error message for expressions containing unsolved metavariables 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-13 13:21:44 -08:00
Leonardo de Moura
12451e4a35 feat(frontends/lean/pp): display implicit arguments when expression contains metavariables 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-13 12:42:05 -08:00
Leonardo de Moura
35bacf95fc feat(shell): provide the default environment when parsing Lua files 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-12 18:21:14 -08:00
Leonardo de Moura
7f818ecd92 feat(library): match procedure for higher-order patterns 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-12 17:45:24 -08:00
Leonardo de Moura
e6c322d97f feat(kernel/free_vars): make free_vars module functions more robust 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-12 17:44:28 -08:00
Leonardo de Moura
29fec3fecc fix(builtin/util): bug incorrect encoding of \t and \n in regular expression, and missing local 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-12 17:40:41 -08:00
Leonardo de Moura
915644f3b3 fix(util/debug): avoid infinite loop when Ctrl-D is pressed after an assertion violation 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-12 17:20:35 -08:00
Leonardo de Moura
5d9a95addd refactor(kernel/free_vars): replace max_free_var with relaxed free_var_range 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-12 17:06:57 -08:00
Leonardo de Moura
582569b793 feat(frontends/lean): allow the user to set the trust_imported flag when creating environments using Lua 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-12 16:46:53 -08:00
Leonardo de Moura
4d9eb4ac6c feat(kernel): add max_free_var function 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-12 16:45:34 -08:00
Leonardo de Moura
6508e63a17 feat(builtin/macros): add assume/take macros for making proof scripts more readable 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-11 18:36:37 -08:00
Leonardo de Moura
781720a26a feat(builtin/kernel): add left_comm theorem 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-11 18:08:08 -08:00
Leonardo de Moura
a1a467a65f refactor(builtin): move congruence theorems to kernel/if_then_else modules 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-11 13:48:28 -08:00
Leonardo de Moura
a0a92f11b7 feat(builtin/congr): add congruence theorems for contextual simplification 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-11 13:37:36 -08:00
Leonardo de Moura
53537d0684 feat(builtin/kernel): 'implication' simplification theorems 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-11 13:35:20 -08:00
Leonardo de Moura
50f281b430 feat(builtin/kernel): add eqf_intro and eqf_elim theorems 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-11 11:13:54 -08:00
Leonardo de Moura
4057f0d2fe feat(emacs): minor improvements to emacs mode 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-11 11:13:20 -08:00
Leonardo de Moura
745c702ffb fix(build): dependency problem on some platforms 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-10 19:06:15 -08:00
Leonardo de Moura
d4a7d796a5 feat(builtin): prove strong induction theorem, add < theorems 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-10 18:46:33 -08:00
Leonardo de Moura
5fb718c03a fix(build): broken dependencies between lean executable and .olean, *_decls.cpp and *_decls.h files 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-10 10:58:35 -08:00
Leonardo de Moura
9e8b083673 feat(emacs): more highlighting 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-09 20:44:01 -08:00
Leonardo de Moura
3008cad151 feat(emacs): highlight tactics 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-09 20:10:57 -08:00
Leonardo de Moura
2cf73fc4d2 feat(emacs): useful abbreviations 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-09 19:57:00 -08:00
Leonardo de Moura
65bdb9c7e0 fix(frontends/lean): unprotected call to Lua API 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-09 19:56:20 -08:00
Leonardo de Moura
411f14415d feat(builtin): automatically generate Lean/C++ interface for builtin theories 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-09 18:09:53 -08:00
Leonardo de Moura
a339a53f50 feat(util/options): 'verbose' as a system option, add -q (quiet) option 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-09 15:31:58 -08:00
Leonardo de Moura
8c41b4e899 feat(build): run tests using -t 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-09 14:12:32 -08:00
Leonardo de Moura
2179e57db3 refactor(builtin): move if_then_else to its own module 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-09 14:08:39 -08:00
Leonardo de Moura
fdeb457a81 feat(kernel/pos_info_provider): add support for file names in pos_info_provider 
The idea is to include the file name when displaying justification objects.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-09 12:19:30 -08:00
Leonardo de Moura
dff0b9011b chore(builtin/cast): cleanup 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-09 12:06:22 -08:00
Leonardo de Moura
3e18cdfeec feat(util/format): do not use colors by default 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-09 11:56:58 -08:00
Leonardo de Moura
6fe362ef07 feat(emacs): include lean-mode Emacs files in the distribution 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-09 11:50:07 -08:00
Leonardo de Moura
84e211b81b fix(frontends/lean): missing ':' in error messages 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-09 11:19:58 -08:00
Leonardo de Moura
f7c7dd4ed4 feat(frontends/lean): include filename in error messages, use GNU error message style 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-09 11:01:27 -08:00
Leonardo de Moura
87b238efcd chore(builtin/kernel): cleanup 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-09 09:00:05 -08:00
Leonardo de Moura
57c0006916 chore(*): cleanup lean builtin symbols, replace :: with _ 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-09 08:33:52 -08:00
Leonardo de Moura
25086947fa fix(builtin/kernel): incorrect comment 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-08 19:14:11 -08:00
Leonardo de Moura
e42b616438 fix(kernel/normalizer): equality between semantic attachments 
Given a heterogenous equality:  a == b
The normalizer will only reduce it if a and b are objects of the same kind.
Now, 1 == true is not reduced to false anymore.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-08 19:10:30 -08:00
Leonardo de Moura
8e9d88c2cf refactor(builtin/kernel): prove iff::intro, and add a new name for it boolext (Boolean extensionality) 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-08 18:31:45 -08:00
Leonardo de Moura
a4b3d6d6c8 refactor(builtin/kernel): prove eta using function extensionality, and rename abst and abstpi to funext and allext 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-08 17:25:14 -08:00
Leonardo de Moura
9c8026b86e refactor(builtin/macros): remove 'take', 'discharge' and 'instantiate' macros 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-08 16:58:01 -08:00
Leonardo de Moura
bdec4c8799 refactor(builtin/Nat): mark constants as opaque 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-08 16:53:08 -08:00
Leonardo de Moura
2e3b92ef36 refactor(builtin/kernel): cleanup 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-08 16:52:43 -08:00
Leonardo de Moura
a6e0dcc96c fix(builtin/cast): remove dominj axiom, it is not consistent with the new semantics of Pi/forall 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-08 16:19:11 -08:00
Leonardo de Moura
57640ecf19 fix(library/elaborator): array bounds 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-08 13:18:49 -08:00
Leonardo de Moura
2b2aa228e3 refactor(builtin/kernel): start with small universes 
The universe constraint manager is more flexible now.
We don't need to start with a huge universe  U >= 512.
We can start small, and increase it on demand.

If module mod1 needs it, it can always add

   universe U >= 3

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-08 12:35:00 -08:00
Leonardo de Moura
cfe576f551 fix(library/elaborator): bug in the elaborator 
The elaborator was not handling correctly constraints of the form

    ctx |- ?m << (Pi x : A, B)
    and
    ctx |- (Pi x : A, B) << ?m

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-08 12:10:50 -08:00
Leonardo de Moura
dd6c13abb0 fix(util/buffer): warning produced by clang++ 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-08 11:27:11 -08:00
Leonardo de Moura
85de05e5cf chore(kernel/unification_constraint): update max_constraint comment to reflect its new semantics 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-08 01:09:47 -08:00
Leonardo de Moura
abf61be8f6 chore(library/tactic): remove imp_tac, it is not needed anymore 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-08 00:57:04 -08:00
Leonardo de Moura
048151487e feat(kernel): use Pi as forall/implication 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-08 00:38:39 -08:00
Leonardo de Moura
e12d6e44cd fix(util/name): bug in Lua API 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 17:52:51 -08:00
Leonardo de Moura
8ce6266e6b feat(library/kernel_bindings): add new predicates for kernel objects in the Lua API 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 17:36:54 -08:00
Leonardo de Moura
6f4ca7bd2a feat(frontends/lean): expose is_explicit function in the Lua API 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 17:36:27 -08:00
Leonardo de Moura
4fdc0406be feat(util/name): additional methods to name Lua API 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 17:35:34 -08:00
Leonardo de Moura
248d55d454 chore(util/script_state): remove dead code 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 16:59:50 -08:00
Leonardo de Moura
2cd2527d9f refactor(shell): move read-eval-loop script to repl.lua 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 16:56:22 -08:00
Leonardo de Moura
0bc2c51c9c fix(build): put back the dependency on lean executable for .olean files 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 16:13:58 -08:00
Leonardo de Moura
d12d0f036f feat(kernel/environment): universe variables now live in their own namespace 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 15:57:36 -08:00
Leonardo de Moura
95515ca5df chore(*): fix warnings produced by clang++ 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 15:39:49 -08:00
Leonardo de Moura
a3af87f8d3 chore(frontends/lean/frontend): remove dead code 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 15:28:21 -08:00
Leonardo de Moura
0363faeec8 fix(frontends/lean/scanner): assertion violation, and add more tests 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 15:12:34 -08:00
Leonardo de Moura
fb73514913 fix(frontends/lean/parser): parser aborted if the scanner throws an exception in the first call to scan(); position information was being shown twice for scanner exceptions 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 15:04:30 -08:00
Leonardo de Moura
f12a76a5cd test(frontends/lean/scanner): missing tests 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 15:03:46 -08:00
Leonardo de Moura
c7338a8eab chore(frontends/lean/scanner): remove dead code 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 14:37:28 -08:00
Leonardo de Moura
29db6accb8 test(tests/lean): new tests for exercising the environment object 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 14:34:21 -08:00
Leonardo de Moura
f67eab000b fix(util/serializer): nontermination on corrupted files 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 14:21:54 -08:00
Leonardo de Moura
d5ddb186d9 feat(library/kernel_bindings): add load method to Lua API 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 14:21:24 -08:00
Leonardo de Moura
6077dc61b7 feat(builtin): remove lean executable as a dependency for builtin .lean files 
Otherwise, we have to rebuild all .lean files whenever we change the executable.
This commit also adds a test for each .lean file.
This is useful for increasing coverage and having a log on how long does it take to process these files.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 13:53:30 -08:00
Leonardo de Moura
0a20356a51 fix(kernel/environment): we should not add an universe contraint object to the set of object when an integer overflow occurs 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 13:43:22 -08:00
Leonardo de Moura
17c4cce89c fix(library/elaborator): remove_detail procedure was keeping a lot of details when typeof_mvar_justification was being used 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 13:24:46 -08:00
Leonardo de Moura
0f1737d62c fix(frontends/lean): more precise position information for infix operators 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 13:19:26 -08:00
Leonardo de Moura
0bdecb6aa4 style(builtin/Nat): name convention 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-07 00:05:51 -08:00
Leonardo de Moura
c5d13abd6f refactor(builtin/Nat): rename destruct to discriminate 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-06 23:05:27 -08:00
Leonardo de Moura
abb9b8af83 fix(frontends/lean): bug in pop::context command, and add new tests for the universe command 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-06 17:14:07 -08:00
Leonardo de Moura
4424a314e0 feat(kernel): add get_universe_distance method 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-06 17:13:13 -08:00
Leonardo de Moura
5fe8c32da9 feat(kernel): use new universe contraints in the environment, allow new constraints to be added 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-06 16:46:11 -08:00
Leonardo de Moura
b5a30855f8 feat(kernel/universe_constraints): add new class for managing universe constraints 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-06 15:01:28 -08:00
Leonardo de Moura
68832dc6f2 fix(builtin/macros): comments 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-06 12:07:13 -08:00
Leonardo de Moura
929a536e2f fix(builtin/README): update documentation 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-06 12:03:11 -08:00
Leonardo de Moura
62bb2ab2f9 fix(builtin/Nat): name convention 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-06 11:41:14 -08:00
Leonardo de Moura
645e748302 feat(frontends/lean): add 'using' command 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-06 11:41:14 -08:00
Leonardo de Moura
8c956280d9 chore(frontends/lean): rename setoption and setopaque commands to set::option and set::opaque 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-06 11:41:03 -08:00
Leonardo de Moura
7222a2d1a9 feat(builtin/kernel): use the same notation for mp, eq::mp and forall::elim 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-05 21:39:31 -08:00
Leonardo de Moura
935c2a03a3 feat(*): change name conventions for Lean builtin libraries 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-05 19:21:44 -08:00
Leonardo de Moura
771b099c0c fix(frontends/lean): must invoke lua GC before closing a scope, reason: we may still have references to the current environment inside of the Lua state object 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-05 16:38:29 -08:00
Leonardo de Moura
9d6bd7501c feat(doc/lean): include lean documentation scripts in the test set 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-05 13:16:47 -08:00
Leonardo de Moura
4ba097a141 feat(frontends/lean): use lowercase commands, replace 'endscope' and 'endnamespace' with 'end' 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-05 13:06:36 -08:00
Leonardo de Moura
6569b07b7c feat(frontends/lean/parser): rename 'show' expression to 'have' 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-05 11:25:58 -08:00
Leonardo de Moura
0b4bdceb10 feat(builtin/macros): rename 'For' macro to 'take' 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-05 11:08:55 -08:00
Leonardo de Moura
9f08156a73 feat(frontends/lean/parser): combine Echo and Show commands into the 'print' command 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-05 11:03:35 -08:00
Leonardo de Moura
ce1213a020 feat(frontends/lean): use '(* ... *)' instead of '(** ... **)' for script code blocks 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-05 10:32:47 -08:00
Leonardo de Moura
028a9bd9bd feat(frontends/lean/scanner): use Lua style comments in Lean 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-05 08:53:27 -08:00
Leonardo de Moura
f5cc2458a9 fix(frontends/lean/parser_calc): missing save calls 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-03 18:26:30 -08:00
Leonardo de Moura
fbe0bccf51 chore(*): name convention, proof construnction functions/macros start with upper-case 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-03 18:11:01 -08:00
Leonardo de Moura
9eb4dc4a81 feat(kernel, library/elaborator, frontends/lean): improve how elaborator_exceptions are displayed in the Lean frontend 
This commit affects different modules.
I used the following approach:
1- I store the metavariable environment at unification_failure_justifications. The idea is to capture the set of instantiated metavariables at the time of failure.
2- I added a remove_detail function. It removes propagation steps from the justification tree object. I also remove the backtracking search space associated with higher-order unificiation. I keep only the search related to case-splits due to coercions and overloads.

3- I use the metavariable environment captured at step 1 when pretty printing the justification of an elaborator_exception.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-03 17:18:23 -08:00
Leonardo de Moura
66ec538c63 doc(doc/lean/calc.md): calculational proof documentation 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-03 11:52:21 -08:00
Leonardo de Moura
5b5cebe750 refactor(builtin/Nat): use obtain-from instead of ExistsElim, and use more user-friendly argument order for Induction 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-03 10:33:57 -08:00
Leonardo de Moura
9f3706e365 feat(builtin/macros): add obtain-from macro for ExistsElim 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-03 10:32:49 -08:00
Leonardo de Moura
d7efdff83d feat(builtin/Nat): add more leq theorems 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-02 22:48:10 -08:00
Leonardo de Moura
cf35e7bed7 feat(frontends/lean): add support for disequalities in calculational proofs 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-02 22:47:45 -08:00
Leonardo de Moura
6329d1828d feat(frontends/lean): reuse name expression 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-02 20:08:21 -08:00
Leonardo de Moura
92c7145d7f feat(kernel/expr): maximize sharing before serializing 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-02 20:03:42 -08:00
Leonardo de Moura
2d5800ace4 feat(builtin/Nat): leq axiom, and some theorems 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-02 18:24:32 -08:00
Leonardo de Moura
9620b00e24 feat(kernel/metavar): is instantiate_metavars, we are also instantiating assigned metavariables that occur in the local context of unassinged ones. 
This modification improves the effectiveness of the process_metavar_inst procedure in the Lean elaborator.

For example, suppose we have the constraint

   ctx |- ?M1[inst:0 ?M2] == a

If ?M1 and ?M2 are unassigned, then we have to consider the two possible solutions:

        ?M1 == a
    or
        ?M1 == #0 and ?M2 == a

On the other hand, if ?M2 is assigned to b, then we can ignore the second case.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-02 16:08:38 -08:00