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Author SHA1 Message Date
Leonardo de Moura
6dfeff92f8 fix(kernel/constraint): add dealloc method 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-28 11:13:51 -07:00
Leonardo de Moura
e3b79730ba fix(kernel/level): initialization error 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-28 11:03:23 -07:00
Leonardo de Moura
2ddadfc920 fix(kernel/environment): compilation errors 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-28 10:58:14 -07:00
Leonardo de Moura
9f57ec059a fix(kernel/constraint): missing inline directive 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-28 10:53:53 -07:00
Leonardo de Moura
272463bd66 feat(kernel/type_checker): add check function 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-28 10:47:50 -07:00
Leonardo de Moura
e769c26800 refactor(kernel): move files that don't need to be in the kernel 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-25 18:30:40 -07:00
Leonardo de Moura
b2518f873d feat(kernel/type_checker): handle ensure_pi when whnf is a meta application 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-25 18:17:32 -07:00
Leonardo de Moura
6b05146eca fix(kernel/type_checker): preserve bound variable name when inferring type of a lambda expression 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-25 17:29:47 -07:00
Leonardo de Moura
63b6564b78 refactor(kernel): define extension_context API for normalizer_extesions and macro_definitions 
A particular macro definition may use the extra information to retrieve information necessary to expand/type a given macro application. Example: it may need to invoke whnf.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-25 15:43:17 -07:00
Leonardo de Moura
4842ae4fc7 refactor(kernel): store macro arguments in the macro_expr 
Before this commit, we "stored" macro arguments using applications.
This representation had some issues. Suppose we use [m a] to denote a macro
application. In the old representation, ([m a] b) and [m a b] would have
the same representation. Another problem is that some procedures (e.g., type inference)
would not have a clean implementation.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-25 15:02:56 -07:00
Leonardo de Moura
9d5ed2bae1 chore(kernel/type_checker): fix style 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-25 12:04:14 -07:00
Leonardo de Moura
a39a5b4195 refactor(kernel): remove normalizer 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-25 12:02:33 -07:00
Leonardo de Moura
a55c3c617d feat(kernel/type_checker): add infer_type 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-25 11:58:29 -07:00
Leonardo de Moura
3e122ed355 feat(kernel/error_msgs): add error message for unsatisfied level constraints, remove messages for dependent pairs 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-25 10:47:05 -07:00
Leonardo de Moura
508bccb0c5 fix(kernel/max_sharing): add example exposing bug in max_sharing_fn, and fix it 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-24 15:55:48 -07:00
Leonardo de Moura
1c8e78e3ae fix(kernel/justification): typo 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-24 15:08:10 -07:00
Leonardo de Moura
4be4f21de6 fix(kernel/type_checker): bug in quick_is_conv, it was not converting free variables to local constants. 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-24 12:46:31 -07:00
Leonardo de Moura
0d7902f9eb feat(kernel/type_checker): finish is_convertible predicate 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-23 20:16:14 -07:00
Leonardo de Moura
e78de448aa feat(kernel/type_checker): add is_convertible predicate (and support for proof irrelevance and eta-reduction) 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-23 19:21:26 -07:00
Leonardo de Moura
cdbef0bf15 fix(kernel/type_checker): is_opaque predicate 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-23 10:51:39 -07:00
Leonardo de Moura
a3554c85fe fix(kernel/definition): clang compilation warning, and add module_idx typedef 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-23 10:50:55 -07:00
Leonardo de Moura
ed37bf650d chore(kernel/environment): fix style 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-22 18:34:55 -07:00
Leonardo de Moura
04a61bdffe feat(kernel/type_checker): remove dead code, add basic whnf procedure 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-22 18:32:50 -07:00
Leonardo de Moura
188da7e4c6 feat(kernel/max_sharing): add method already_processed 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-22 18:30:07 -07:00
Leonardo de Moura
9fda7e2529 fix(kernel): incorrect optimization in max_sharing_fn class 
The resultant expression may failed to be fully shared.
Add an example that demonstrates the problem.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-22 15:38:22 -07:00
Leonardo de Moura
086dd6b1a1 chore(kernel/environment): fix style 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-22 15:36:52 -07:00
Leonardo de Moura
cc1cfba8ad refactor(kernel/type_checker): new API for type checker 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-21 16:12:47 -07:00
Leonardo de Moura
6417c79569 feat(kernel/environment): add is_descendant method 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-21 14:28:50 -07:00
Leonardo de Moura
bfeb51ce58 feat(kernel/environment): add trust level field 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-21 13:39:47 -07:00
Leonardo de Moura
ee58a83e25 chore(kernel): remove unnecessary files 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-18 14:25:09 -07:00
Leonardo de Moura
d0dc16355b chore(kernel): remove unnecessary file 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-18 14:23:32 -07:00
Leonardo de Moura
582352d647 refactor(kernel/environment): simplified (functional) environment object 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-18 14:21:49 -07:00
Leonardo de Moura
234abb1238 feat(kernel/definition): default constructor for definitions 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-18 13:10:05 -07:00
Leonardo de Moura
984ac03ac7 refactor(kernel): replace kernel object with definition, disable affected files 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-17 16:10:47 -07:00
Leonardo de Moura
cb479a75ae fix(kernel/expr): make sure we cannot create a free variable with index uint_max, reason: get_free_var_range would return an incorrect value 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-17 13:25:21 -07:00
Leonardo de Moura
3712da0b54 refactor(kernel/instantiate): use get_free_var_range to improve instantiate, remove instantiate_with_closed, fix index overflow bug 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-17 13:12:49 -07:00
Leonardo de Moura
1fd5e9682d refactor(kernel/free_vars): use get_free_var_range to improve lift_free_vars and lower_free_vars performance 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-17 12:41:06 -07:00
Leonardo de Moura
4ae958af56 refactor(kernel/free_vars): use get_free_var_range to improve has_free_var_in_range performance 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-17 12:18:19 -07:00
Leonardo de Moura
dc864bf7b9 feat(kernel): store free variable range in composite expressions 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-17 11:31:48 -07:00
Leonardo de Moura
bc8379256a refactor(kernel): remove pairs from kernel 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-04-17 10:52:07 -07:00
Leonardo de Moura
fb2ec8fb12 fix(kernel): style 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:57 -07:00
Leonardo de Moura
9b161b825f refactor(kernel): instantiate_params 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:57 -07:00
Leonardo de Moura
3651b4ecd0 refactor(kernel): replace_fn functional object 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:57 -07:00
Leonardo de Moura
3939b93c2d refactor(kernel): substitution 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:57 -07:00
Leonardo de Moura
25948ac534 refactor(kernel): cleanup interfaces 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:57 -07:00
Leonardo de Moura
08087ea9c6 refactor(kernel): remove dead code 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:57 -07:00
Leonardo de Moura
eb487e44c1 refactor(kernel): use names instead of unsigned integers to encode level parameters 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:57 -07:00
Leonardo de Moura
ddbb3a7944 refactor(kernel): add error msg formatters, remove unnecessary files, add new type_checker interface 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:57 -07:00
Leonardo de Moura
916301bdfb refactor(kernel): parametric kernel objects 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:57 -07:00
Leonardo de Moura
54801bbd05 refactor(kernel): constraints 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:57 -07:00
Leonardo de Moura
aa4a7acccf feat(kernel/level): is_trivial predicate for level constraints 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:57 -07:00
Leonardo de Moura
4b7fe064fe refactor(kernel): finish formatter interface 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:56 -07:00
Leonardo de Moura
bf13441bd7 fix(kernel): bugs in justification module, add missing metavar methods, add basic metavar tests 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:56 -07:00
Leonardo de Moura
4c30ea9251 fix(kernel/justification): none is the unit of mk_composite 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:56 -07:00
Leonardo de Moura
3c6002e969 refactor(kernel): add mk_rev_app, update_rev_app, implement instantiate_metavars functions, modify instantiate (free vars) API 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:56 -07:00
Leonardo de Moura
42e253c962 fix(*): style and clang warnings 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:56 -07:00
Leonardo de Moura
968c0d799f refactor(kernel): implement substitution methods 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:56 -07:00
Leonardo de Moura
5f4b1cf47e feat(kernel): define metavar substitution based on red-black trees 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:56 -07:00
Leonardo de Moura
fdde12e6af refactor(kernel): remove unnecessary files 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:56 -07:00
Leonardo de Moura
2a73389ed3 refactor(kernel): justification objects 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:56 -07:00
Leonardo de Moura
501435f6fc feat(kernel): add has_local predicate 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:56 -07:00
Leonardo de Moura
997f32378c refactor(kernel): remove unnecessary files 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:56 -07:00
Leonardo de Moura
6baa59376c refactor(kernel): normalizer 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:56 -07:00
Leonardo de Moura
eb046c11fb refactor(kernel): the type in let-exprs is not optional anymore, if the user does not provide it, we use a metavariable 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:55 -07:00
Leonardo de Moura
410d5cc8ed fix(kernel): remove unnecessary file 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:55 -07:00
Leonardo de Moura
16aa1ebbac refactor(kernel): replace_visitor 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:55 -07:00
Leonardo de Moura
101888e079 refactor(kernel): delete update_expr 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:55 -07:00
Leonardo de Moura
b5f0f28009 refactor(kernel): environment, kernel object and exceptions 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:55 -07:00
Leonardo de Moura
737fe6830f test(tests/kernel): adjust expr tests 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:55 -07:00
Leonardo de Moura
f986963a95 refactor(kernel): serializer and deserializer 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:55 -07:00
Leonardo de Moura
74f74d2f79 refactor(kernel): shallow copy procedure 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:55 -07:00
Leonardo de Moura
5da501d538 fix(kernel): style warnings 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:55 -07:00
Leonardo de Moura
73c8bf4436 refactor(tests/kernel): move tests to new kernel 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:55 -07:00
Leonardo de Moura
565dbe1700 fix(kernel/instantiate): bug in new head_beta_reduce 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:55 -07:00
Leonardo de Moura
d17990ed78 refactor(kernel): add formatter and simplify contexts 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:55 -07:00
Leonardo de Moura
53ee205dc6 fix(kernel): memory corruption bugs 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:55 -07:00
Leonardo de Moura
72e1678ad9 refactor(kernel): cleanup instantiate and abstract procedures, implement update procedures 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:55 -07:00
Leonardo de Moura
db31cc37a1 refactor(kernel/free_vars): cleanup free_vars procedures 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:55 -07:00
Leonardo de Moura
533f44e224 refactor(kernel/expr): for_each_fn, replace_fn, and find_fn without templates 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:55 -07:00
Leonardo de Moura
69b9f2dd37 refactor(kernel/expr): for_each and find functional objects 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:54 -07:00
Leonardo de Moura
23988f528c refactor(kernel/expr): add expr constructors, and expression equality test 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:54 -07:00
Leonardo de Moura
9d3db8de1f fix(kernel/diff_cnstrs): missing include 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:54 -07:00
Leonardo de Moura
02413d7c44 refactor(kernel/expr): adding suport for universe polymorphism, and simplify metavariable representation 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:54 -07:00
Leonardo de Moura
13cfd60622 fix(kernel/diff_cnstrs): copyright msg 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:54 -07:00
Leonardo de Moura
76b1ddb967 feat(kernel): add difference constraint solver with backtracking support, and justification generation, this solver will be used to check the satisfiability of universe level constraints 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:54 -07:00
Leonardo de Moura
9f93b5d97e feat(kernel/level): new universe level datastructure for universe level polymorphism 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:54 -07:00
Leonardo de Moura
1b6b33b3f5 refactor(kernel): start version 0.2, new kernel with universe polymorphism and better/cleaner support for metavariables 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-03-18 10:27:54 -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
c526e5ec00 feat(builtin/kernel): prove false_elim without using case 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-15 14:26:13 -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
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
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
f28c56b188 feat(builtin/num): add auxiliary definitions and theorems for proving the primitive recursion theorem 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-08 19:36:17 -08:00
Leonardo de Moura
24528ff685 fix(library/elaborator): fix glitches in the elaborator that were forcing us to provide parameters explicitly 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-07 18:02:08 -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
6d7ec9d7b6 refactor(kernel): add heterogeneous equality back to expr 
The main motivation is that we will be able to move equalities between universes.

For example, suppose we have
    A : (Type i)
    B : (Type i)
    H : @eq (Type j) A B
where j > i

We didn't find any trick for deducing (@eq (Type i) A B) from H.
Before this commit, heterogeneous equality as a constant with type

   heq : {A B : (Type U)} : A -> B -> Bool

So, from H, we would only be able to deduce

   (@heq (Type j) (Type j) A B)

Not being able to move the equality back to a smaller universe is
problematic in several cases. I list some instances in the end of the commit message.

With this commit, Heterogeneous equality is a special kind of expression.
It is not a constant anymore. From H, we can deduce

   H1 : A == B

That is, we are essentially "erasing" the universes when we move to heterogeneous equality.
Now, since A and B have (Type i), we can deduce (@eq (Type i) A B) from H1. The proof term is

  (to_eq (Type i) A B (to_heq (Type j) A B H))  :  (@eq (Type i) A B)

So, it remains to explain why we need this feature.

For example, suppose we want to state the Pi extensionality axiom.

axiom hpiext {A A' : (Type U)} {B : A → (Type U)} {B' : A' → (Type U)} :
      A = A' → (∀ x x', x == x' → B x == B' x') → (∀ x, B x) == (∀ x, B' x)

This axiom produces an "inflated" equality at (Type U) when we treat heterogeneous
equality as a constant. The conclusion

     (∀ x, B x) == (∀ x, B' x)

is syntax sugar for

   (@heq (Type U) (Type U) (∀ x : A, B x) (∀ x : A', B' x))

Even if A, A', B, B' live in a much smaller universe.

As I described above, it doesn't seem to be a way to move this equality back to a smaller universe.

So, if we wanted to keep the heterogeneous equality as a constant, it seems we would
have to support axiom schemas. That is, hpiext would be parametrized by the universes where
A, A', B and B'. Another possibility would be to have universe polymorphism like Agda.
None of the solutions seem attractive.

So, we decided to have heterogeneous equality as a special kind of expression.
And use the trick above to move equalities back to the right universe.

BTW, the parser is not creating the new heterogeneous equalities yet.
Moreover, kernel.lean still contains a constant name heq2 that is the heterogeneous
equality as a constant.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-07 10:28:10 -08:00
Leonardo de Moura
30570c843f feat(builtin): add optional type 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-02-05 17:33:06 -08:00