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Author SHA1 Message Date
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
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
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
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
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
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
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
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
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
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
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
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
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
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
Leonardo de Moura
ecc5d1bc3a refactor(kernel): move printer to library, cleanup io_state interface 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-02 13:37:50 -08:00
Leonardo de Moura
0592261847 refactor(kernel/io_state): move io_state_stream to library 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-02 13:14:21 -08:00
Leonardo de Moura
b81d3309b9 fix(kernel): remove ios hack 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-02 13:03:25 -08:00
Leonardo de Moura
43909ca66b feat(frontends/lean/pp): pretty print SetOpaque command 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-01 13:16:44 -08:00
Leonardo de Moura
74cae2a154 refactor(library/elaborator): remove hackish rule 
After the recent fixes, the hack in process_metavar is not needed anymore.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-01 10:55:39 -08:00
Leonardo de Moura
cbd1f98365 fix(library/elaborator): bug at method process_metavar_inst, add new test that exposed the bug 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2014-01-01 03:02:41 -08:00
Leonardo de Moura
0d815b8594 refactor(kernel/context): hide that the context is implemented using lists 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-31 19:43:50 -08:00
Leonardo de Moura
1cb7408c46 fix(kernel/normalizer): metavariable reification was incorrect, add tst11 at tests/kernel/normalizer.cpp to expose the bug 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-31 16:24:36 -08:00
Leonardo de Moura
cd3bbb1ebf fix(kernel/builtin): enforcing design decision: semantic attachments are NOT simplifiers, they should do only evaluation 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-31 10:14:17 -08:00
Leonardo de Moura
c485b4bc4c fix(kernel/environment): binary file reader, force the file to be read in binary mode 
We need this flag to be able to read the file on Windows.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-30 18:20:40 -08:00
Leonardo de Moura
1f6e959139 feat(deserializer): protect against corrupted binary files 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-30 18:05:38 -08:00
Leonardo de Moura
a80fccea93 chore(*): cleanup builtin registration 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-30 12:19:00 -08:00
Leonardo de Moura
2a2f0b0d89 refactor(kernel/builtin): move helper decl macros to a separate file 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-30 11:51:30 -08:00
Leonardo de Moura
ecd62a1783 refactor(builtin/basic): rename basic.lean to kernel.lean 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-30 11:46:03 -08:00
Leonardo de Moura
72761f14e4 refactor(library/io_state): move to the kernel 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-30 11:20:23 -08:00
Leonardo de Moura
097b10e424 refactor(kernel/builtin): move builtin declarations to basic 
There is a lot to be done. We should do the same for Nat, Int and Real.
We also should cleanup the file builtin.cpp and builtin.h.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-29 22:00:03 -08:00
Leonardo de Moura
37e8738a5f refactor(kernel/expr): value deserializer 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-29 20:47:14 -08:00
Leonardo de Moura
de77851a00 refactor(util/object_serializer): add methods write_core and read_core that allows to pack information in the byte used to indicate whether an object is already in the cache or not 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-29 19:59:53 -08:00
Leonardo de Moura
dbd122301a feat(kernel/object): compact object serialization kind ids 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-29 19:19:24 -08:00
Leonardo de Moura
d0fdc3619b feat(kernel/expr): compress application serialization 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-29 19:11:57 -08:00
Leonardo de Moura
14c3e11289 refactor(kernel/builtin): emove mk_bin_rop and mk_bin_lop to library 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-29 15:23:18 -08:00
Leonardo de Moura
92404c511c refactor(kernel/builtin): Bool type does not need to be a semantic attachment 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-29 15:12:08 -08:00
Leonardo de Moura
dfe46b9d25 refactor(kernel/builtin): move definition and axioms to basic.lean 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-29 14:01:30 -08:00
Leonardo de Moura
1b300d3598 chore(kernel/builtin): remove unnecessary functions 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-29 12:55:51 -08:00
Leonardo de Moura
df3686634d refactor(kernel/builtin): remove unnecessary predicates 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-29 12:20:29 -08:00
Leonardo de Moura
9fdf2a3f55 feat(kernel): add trust_imported flag, it skips type checking of 'pre-compiled' Lean modules 
"Pre-compiled" .olean files were already type checked. The flag -t instructs to Lean to skip
type checking when importing these files.
TODO: add a check-sum.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-29 03:43:53 -08:00
Leonardo de Moura
411ebbc3c1 refactor(library/basic_thms): move the proof of all basic theorems to a .Lean file 
This commit also adds several new theorems that are useful for implementing the simplifier.
TODO: perhaps we should remove the declarations at basic_thms.h?

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-29 03:04:49 -08:00
Leonardo de Moura
5e0b344871 fix(kernel/object): uninitialized variable 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-28 21:57:56 -08:00
Leonardo de Moura
41c1010043 feat(frontends/lean/parser): make Import command use binary Lean files 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-28 19:20:04 -08:00
Leonardo de Moura
aee1c6d3f3 feat(kernel): export/import (.olean) binary files 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-28 17:31:35 -08:00
Leonardo de Moura
22bebbf242 feat(kernel/object): serializer for kernel objects 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-28 14:39:10 -08:00
Leonardo de Moura
755e8b735f feat(kernel/expr): serializer for kernel expressions 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-28 01:23:21 -08:00
Leonardo de Moura
0ef8ba2939 feat(kernel/level): serializer for level objects 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-27 23:30:13 -08:00
Leonardo de Moura
8cf65f354b fix(frontends/lean/pp): forall and exists pretty printing when used as constants 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-27 12:50:41 -08:00
Leonardo de Moura
2aa691ccb3 fix(kernel/replace_fn): ignore the cached type in constants 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-24 21:11:25 -08:00
Leonardo de Moura
1a0f0c1609 feat(kernel/normalizer): let normalizer ignore 'undefined' constants 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-24 20:54:15 -08:00
Leonardo de Moura
6cc57cc4b5 fix(library/tactic/apply_tactic): bug in apply_tac 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-24 15:54:56 -08:00
Leonardo de Moura
cb95b14332 feat(library/tactic/apply_tactic): improve apply_tactic 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-24 14:23:06 -08:00
Soonho Kong
de018220e1 feat(*): use std::make_shared to create shared_ptr 2013-12-24 14:32:50 -05:00
Leonardo de Moura
b83b17d3ab fix(kernel/metavar): bug at cached_metavar_env::update method 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-23 15:41:02 -08:00
Leonardo de Moura
3e32d9bef2 feat(library/tactic): add support for Pi's at to_proof_state 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-22 16:40:55 -08:00
Leonardo de Moura
4229e498d2 refactor(kernel/type_checker): combine type_checker and type_inferer into a single class, and avoid code duplication 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-22 11:51:38 -08:00
Leonardo de Moura
9128a437b8 refactor(library/cast): replace cast semantic attachment with axioms, add heterogeneous symmetry axiom 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-21 18:23:37 -08:00
Leonardo de Moura
90dbdaec40 feat(kernel/expr): cache is_arrow result 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-21 13:59:45 -08:00
Leonardo de Moura
1faf42e2e1 chore(kernel/expr): remove unnecessary #if-#then-#else 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-21 13:36:41 -08:00
Leonardo de Moura
7b0b363b32 fix(kernel/normalizer): metavariable reification 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-21 06:40:26 -08:00
Leonardo de Moura
84df182beb refactor(kernel/instantiate): remove hackish (dead) function 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-20 14:37:05 -08:00
Leonardo de Moura
7772c16033 refactor(kernel): add unfold_opaque flag to normalizer, modify how type checker uses the opaque flag, remove hidden_defs, and mark most builtin definitions as opaque 
After this commit, in the type checker, when checking convertability, we first compute a normal form without expanding opaque terms.
If the terms are convertible, then we are done, and saved a lot of time by not expanding unnecessary definitions.
If they are not, instead of throwing an error, we try again expanding the opaque terms.
This seems to be the best of both worlds.
The opaque flag is a hint for the type checker, but it would never prevent us from type checking  a valid term.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-20 12:47:47 -08:00
Leonardo de Moura
026f666526 feat(kernel/type_checker): use expression before normalization in the unification constraints generated by the typechecker 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-20 11:22:13 -08:00
Leonardo de Moura
4838c055b8 feat(kernel/environment): add set_opaque method 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-20 10:45:44 -08:00
Leonardo de Moura
46627289b8 fix(kernel/expr): avoid '_' as a binder name, we use '_' as a placeholder in the Lean frontend 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-19 14:47:53 -08:00
Leonardo de Moura
6cc83dbe2a fix(kernel/kernel_exception): incorrect pp method 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-19 14:46:22 -08:00
Leonardo de Moura
47c7bb1bde refactor(*): uses aliases for unordered_map and unordered_set 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-18 12:30:45 -08:00
Leonardo de Moura
1e4fa76a47 feat(util/name_map): add template alias 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-18 11:34:40 -08:00
Leonardo de Moura
7b2fea3fab fix(kernel/normalizer): compilation problem with clang++ 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-18 08:46:36 -08:00
Leonardo de Moura
418623b874 feat(kernel/replace_fn): add template replace that captures commonly used pattern 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-17 18:31:59 -08:00
Leonardo de Moura
23e518001a feat(kernel/normalizer): avoid unnecessary creation of closures for n-ary functions 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-17 18:10:13 -08:00
Leonardo de Moura
10f28c7bec feat(kernel/replace_fn): non-recursive replace_fn 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-17 16:35:39 -08:00
Leonardo de Moura
af4a6c9364 fix(kernel/normalizer): cache problems 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-17 14:52:14 -08:00
Leonardo de Moura
33789fad4c fix(kernel/builtin): make sure the if-then-else semantic attachment is not a simplifier 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-17 14:34:40 -08:00
Leonardo de Moura
c53233ea26 fix(kernel/normalizer): avoid svalue hack, use 'semantic attachments' for implementing closures, include context in the closure 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-17 14:33:42 -08:00
Leonardo de Moura
836357c65c fix(kernel/normalizer): bug in Let normalization 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-17 12:35:25 -08:00
Leonardo de Moura
84bfe2a222 fix(library/elaborator): bug in process_meta_app 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-17 10:56:20 -08:00
Leonardo de Moura
f09fd0fc04 feat(kernel/printer): include de Bruijn index in the debug printer 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-16 16:56:46 -08:00
Leonardo de Moura
af42078205 fix(kernel): incorrect use of scoped_map 
This commit also adds a new test that exposes the problem.
The scoped_map should not be used for caching values in the normalizer and type_checker. When we extend the context, the meaning of all variables is modified (we are essentially performing a lift). So, the values stored in the cache are not correct in the new context.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-16 15:11:39 -08:00
Leonardo de Moura
02ee31b786 feat(kernel/normalizer): provide the metavar_env to instantiate and add_inst in the normalizer, it will minimize the number of local_entries needed 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-14 15:41:50 -08:00
Leonardo de Moura
3d30664611 feat(kernel/type_checker): provide the metavar_env to instantiate, it will minimize the number of local_entries needed 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-14 15:13:56 -08:00
Leonardo de Moura
4357c9196e feat(kernel/metavar): make sure that a metavariable 'm' can only be assigned to a term that contains free variables available in the context associated with 'm' 
This commit also simplifies the method check_pi in the type_checker and type_inferer.
It also fixes process_meta_app in the elaborator.
The problem was in the method process_meta_app and process_meta_inst.
They were processing convertability constrains as equality constraints.
For example, process_meta_app would handle

    ctx |- Type << ?f b

as

    ctx |- Type =:= ?f b

This is not correct because a ?f that returns (Type U) for b satisfies the first but not the second.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-14 12:25:00 -08:00
Leonardo de Moura
51aee83b70 refactor(kernel/metavar_env): use the same approach used in the class environment in the class metavar_env 
This modification was motivated by a bug exposed by tst17 at tests/kernel/type_checker.
metavar_env is now a smart point to metavar_env_cell.
ro_metavar_env is a read-only smart pointer. It is useful to make sure we are using proof_state correctly.

example showing that the approach for caching metavar_env is broken in the type_checker

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-13 18:59:15 -08:00
Leonardo de Moura
2e5e5e187f chore(util/rc): remove unnecessary argument from LEAN_COPY_REF and LEAN_MOVE_REF macros 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-13 15:01:24 -08:00
Leonardo de Moura
fa8b984e27 fix(kernel/environment): compilation warnings 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-13 13:54:45 -08:00
Leonardo de Moura
ae52c8062e chore(kernel/metavar): remove unused function 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-12 17:39:14 -08:00
Leonardo de Moura
450d6a4b1e refactor(util/splay_tree): replace find with splay_find 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-12 17:27:30 -08:00
Leonardo de Moura
f97c260b0b refactor(kernel/environment): add ro_environment 
The environment object is a "smart-pointer".
Before this commit, the use of "const &" for environment objects was broken.
For example, suppose we have a function f that should not modify the input environment.
Before this commit, its signature would be
       void f(environment const & env)
This is broken, f's implementation can easilty convert it to a read-write pointer by using
the copy constructor.
       environment rw_env(env);
Now, f can use rw_env to update env.

To fix this issue, we now have ro_environment. It is a shared *const* pointer.
We can convert an environment into a ro_environment, but not the other way around.

ro_environment can also be seen as a form of documentation.
For example, now it is clear that type_inferer is not updating the environment, since its constructor takes a ro_environment.

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-12 16:48:34 -08:00
Leonardo de Moura
7b2cbd6926 chore(kernel/environment): remove implementation hack 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-12 16:48:34 -08:00
Leonardo de Moura
3457fe5935 chore(kernel): rename read_only_environment and read_write_environment 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-12 16:48:33 -08:00
Leonardo de Moura
1852c86948 feat(kernel): improve instantiate and lift_free_vars (use metavar_env to minimize the number of lift and inst local_entries needed) 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-12 16:48:33 -08:00
Leonardo de Moura
058bdb88ac feat(kernel/context): add operator== for contexts, and new constructor 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-12 16:48:33 -08:00
Leonardo de Moura
38a25a1bd2 feat(kernel/metavar): (re-)enable add_lift simplification 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-12 16:48:33 -08:00
Leonardo de Moura
98f5ce0512 fix(kernel/context): unused var warning in release mode 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2013-12-11 21:24:05 -08:00