michael/lean2
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions
5592 commits 3 branches 0 tags 28 MiB
Commit graph

4298 commits

Author SHA1 Message Date
Leonardo de Moura
014271da8b feat(frontends/lean): better error messages for ill-terminated declarations 2015-02-10 14:38:00 -08:00
Leonardo de Moura
058377c8c6 feat(library/tactic/rewrite_tactic): treat iff.refl as trivial step in the rewrite tactic 2015-02-08 17:27:59 -08:00
Leonardo de Moura
666f697d24 fix(frontends/lean/builtin_exprs): 'using' expression should make local constant available for tactics 2015-02-08 17:27:22 -08:00
Leonardo de Moura
fcd67649ed refactor(kernel): expose may_reduce_later method 2015-02-07 20:36:26 -08:00
Leonardo de Moura
b57f93bad5 refactor(kernel): remove unnecessary procedures 2015-02-07 20:14:19 -08:00
Leonardo de Moura
1bdf7ae55a feat(kernel/default_converter): make norm_ext virtual 2015-02-07 19:25:56 -08:00
Leonardo de Moura
4c2277fccf feat(kernel/converter): more cleanup 2015-02-07 19:19:01 -08:00
Leonardo de Moura
73acaca21e refactor(kernel/default_converter): remove extra_opaque_pred 2015-02-07 19:05:46 -08:00
Leonardo de Moura
a11d1efb42 refactor(kernel/converter): remove mk_default_converter procedures 2015-02-07 19:03:58 -08:00
Leonardo de Moura
a47615009f refactor(kernel/type_checker): replace mk_default_converter with default_converter 2015-02-07 19:01:59 -08:00
Leonardo de Moura
f018fdabb9 refactor(library/kernel_bindings): remove unnecessary procedure 2015-02-07 18:57:46 -08:00
Leonardo de Moura
1640568f6a refactor(library/reducible): use default_converter in reducible, and converters based on reducible hints 2015-02-07 17:31:53 -08:00
Leonardo de Moura
7823905fc1 fix(kernel/default_converter): use is_opaque at is_delta 2015-02-07 17:30:36 -08:00
Leonardo de Moura
b4f1029318 refactor(library/reducible): define opaque_type_checker using default_converter 2015-02-07 17:05:29 -08:00
Leonardo de Moura
e04250f0d8 refactor(library/tactic/rewrite_tactic): use default_converter 2015-02-07 16:44:51 -08:00
Leonardo de Moura
c04c0e8381 refactor(*): remove transparent_scope hack, replace [strict] with [all-transparent] annotation 2015-02-07 15:19:41 -08:00
Leonardo de Moura
7945b8adab refactor(kernel/type_checker): remove useless procedures 2015-02-07 14:55:36 -08:00
Leonardo de Moura
12d320fa19 refactor(kernel/default_converter): avoid carrying type_checker and delayed_justification around in the default_converter 2015-02-07 14:10:56 -08:00
Leonardo de Moura
71b9215a70 refactor(kernel/default_converter): cleanup 2015-02-07 13:49:42 -08:00
Leonardo de Moura
3f06f7b6fd refactor(kernel): move default_converter to its own module 2015-02-07 11:33:37 -08:00
Leonardo de Moura
c2a296b1de feat(library/tactic/apply_tactic): add flag for disabling class instance resolution in the apply tactic 2015-02-06 17:27:24 -08:00
Leonardo de Moura
1557a579ed feat(library/tactic/proof_state): add report_failure flag to proof state 
tactic can use the flag to produce nice error messages
 2015-02-06 16:29:04 -08:00
Leonardo de Moura
2126b8ec9a feat(library/tactic/apply_tactic): perform class-instance resolution in the apply tactic 
closes #360
 2015-02-06 16:14:03 -08:00
Leonardo de Moura
18808d133e refactor(library/tactic/goal): move goal => local_context conversion to goal class 2015-02-06 16:09:59 -08:00
Leonardo de Moura
f10424d729 fix(library/tactic/rewrite_tactic): memory leak 2015-02-06 15:24:09 -08:00
Leonardo de Moura
1e8a975daa feat(frontends/lean): extend parser: rewrite "fold" step 2015-02-06 15:22:34 -08:00
Leonardo de Moura
aa70334f8d feat(library/tactic/rewrite_tactic): add "fold" step 2015-02-06 15:21:49 -08:00
Leonardo de Moura
47bd5e53e2 fix(library/tactic/rewrite_tactic): memory leak 2015-02-06 14:24:10 -08:00
Leonardo de Moura
5b25da8c43 feat(frontends/lean): add esimp tactic based on rewrite tactic 
closes #358
 2015-02-06 14:13:32 -08:00
Leonardo de Moura
7aac9f1fdb feat(library/tactic/rewrite_tactic): use expensive convertability checker at reduce_to steps and trivial goal 2015-02-06 13:53:03 -08:00
Leonardo de Moura
5b2a9dacc2 fix(library/tactic/rewrite_tactic): matcher should unfold only reducible constants 2015-02-06 13:44:04 -08:00
Leonardo de Moura
b4139627e5 feat(library/tactic/rewrite_tactic): add option to prevent any kind of constant unfolding when perfoming pattern matching in the rewrite tactic 2015-02-06 13:27:33 -08:00
Leonardo de Moura
62daf73dd0 chore(library/normalize): fix style 2015-02-06 13:27:10 -08:00
Leonardo de Moura
ba9557bb94 fix(library/tactic/rewrite_tactic): incorrect assertion 2015-02-06 13:02:50 -08:00
Leonardo de Moura
979d6494e9 feat(emacs/lean-syntax): add syntax-highlight for unfold-c hint attribute 2015-02-06 12:57:11 -08:00
Leonardo de Moura
bc95f09828 feat(frontends/lean/decl_cmds): allow user to specify unfold-c hint 2015-02-06 12:56:52 -08:00
Leonardo de Moura
ba641d7c58 feat(library/normalize): validate unfold-c hints 2015-02-06 12:42:53 -08:00
Leonardo de Moura
7205382f8c feat(library/definitional/projection): add "unfold-c" hint to projections 2015-02-06 12:39:57 -08:00
Leonardo de Moura
1bd1f94542 feat(library/normalize): add "unfold-c" hint to normalizer 
This hint will also be used in the simplifier
 2015-02-06 12:39:49 -08:00
Leonardo de Moura
39446a7215 refactor(library/projection): move is_constructor_app to util 2015-02-06 12:12:25 -08:00
Leonardo de Moura
1043cc8b48 feat(library/normalize): add templates for serializing optional types 2015-02-06 11:59:30 -08:00
Leonardo de Moura
2e626b29fb feat(library/tactic/rewrite_tactic): allow many constants to be provided in a single rewrite unfold step 2015-02-06 11:03:36 -08:00
Leonardo de Moura
56a46ae61e feat(frontends/lean/parse_tactic_location): make rewrite notation more uniform 2015-02-06 10:31:50 -08:00
Leonardo de Moura
264cedb3a6 fix(frontends/lean/rewrite_tactic): incorrect assertion 2015-02-05 20:02:49 -08:00
Leonardo de Moura
e17ba27596 fix(library/tactic/rewrite_tactic): adjust the behavior of class resolution in rewriter 
The solution is not very satisfactory. I should investigate it more.
 2015-02-05 19:08:47 -08:00
Leonardo de Moura
ffe0d1186e feat(library/tactic/rewrite_tactic): add "reduce_to" step at rewrite tactic 2015-02-05 13:59:55 -08:00
Leonardo de Moura
116c65bff5 feat(library/tactic/rewrite_tactic): add reduction step to rewrite tactic 2015-02-05 13:42:50 -08:00
Leonardo de Moura
38ab4e7b3a feat(frontends/lean/parse_rewrite_tactic): extend rewrite tactic parser 
Add support for reduction steps.
 2015-02-05 13:24:37 -08:00
Leonardo de Moura
7cdc88701d feat(library/tactic/rewrite_tactic): add "reduction" step to rewrite tactic 2015-02-05 13:16:05 -08:00
Leonardo de Moura
808521223b feat(library/tactic/rewrite_tactic): support constant unfolding in rewrite tactic 2015-02-05 12:58:30 -08:00
Leonardo de Moura
5443609845 fix(frontends/lean/parse_rewrite_tactic): take namespaces into account when parsing constant to unfold 2015-02-05 12:41:11 -08:00
Leonardo de Moura
d6958be7e7 fix(library/tactic/location): replace cache must not be used when only a subset of all occurrences should be replaced at replace_occurrences 2015-02-05 10:50:40 -08:00
Leonardo de Moura
bc8bb1dbd3 feat(kernel/replace_fn): add use_cache flag to replace function 2015-02-05 10:49:18 -08:00
Leonardo de Moura
b6dd1269b9 feat(frontends/lean/builtin_exprs): make 'obtain' arguments visible by default 2015-02-05 10:38:45 -08:00
Leonardo de Moura
dfad24e3f5 feat(frontends/lean): polish rewrite tactic notation 2015-02-05 10:15:58 -08:00
Leonardo de Moura
941b493835 chore(library/tactic/rewrite_tactic): modify param name 2015-02-05 10:04:03 -08:00
Leonardo de Moura
0abfa30ead fix(library/tactic/rewrite_tactic): elaboration bug in the rewrite tactic steps/elements 2015-02-05 10:01:18 -08:00
Leonardo de Moura
15efadfbdc feat(frontends/lean/parse_rewrite_tactic): cleanup rewrite tactic notation 
Make a rewrite command sequence explicit.
 2015-02-04 20:16:24 -08:00
Leonardo de Moura
14c72e82f6 feat(library/tactic/rewrite_tactic): add support for rewriting hypotheses 2015-02-04 20:04:19 -08:00
Leonardo de Moura
08dcc9e2fc feat(frontends/lean/parse_rewrite_tactic): polish rewrite tactic notation 2015-02-04 19:19:19 -08:00
Leonardo de Moura
55fb678db2 fix(library/tactic/location): clang++ 3.3 compilation problem 2015-02-04 18:48:23 -08:00
Leonardo de Moura
42c2f7eb11 fix(library/tactic/rewrite_tactic): memory leak 2015-02-04 18:40:11 -08:00
Leonardo de Moura
89fde9d829 feat(library/tactic/rewrite_tactic): add maximum number of iterations threshold to rewrite tactic 
The idea is to avoid nontermination.
 2015-02-04 16:13:15 -08:00
Soonho Kong
ca16381892 feat(bin): add linja.in and LEAN_BIN_DEP cmake option 
see the discussion in issue #422
 2015-02-04 15:46:08 -08:00
Leonardo de Moura
dc297865d4 chore(library/tactic/rewrite_tactic): fix compilation warnings 2015-02-04 15:34:02 -08:00
Leonardo de Moura
ee079d12f4 feat(library/tactic/rewrite_tactic): remove trivial goal in rewrite_tactic 2015-02-04 15:29:52 -08:00
Leonardo de Moura
f0fac1ae0e feat(library/constants): add eq.intro 2015-02-04 15:27:18 -08:00
Leonardo de Moura
e5381679d6 feat(library/tactic/rewrite_tactic): rewrite goal 2015-02-04 15:17:58 -08:00
Leonardo de Moura
599de0271b feat(frontends/lean/parse_tactic_location): validate occurrence index 2015-02-04 14:04:56 -08:00
Leonardo de Moura
09818adf90 feat(library/tactic/rewrite_tactic): elaborate rewrite rule using unifier 2015-02-04 13:51:32 -08:00
Leonardo de Moura
49323ab598 feat(library/util): add mk_symm 2015-02-04 13:44:55 -08:00
Leonardo de Moura
ccae014ef9 feat(library/tactic/rewrite_tactic): ignore inst_implicit arguments when matching applications of declarations which contain them 2015-02-04 12:14:47 -08:00
Leonardo de Moura
0e05c239a5 feat(library/tactic/rewrite_tactic): add custom matcher pluging for rewriter 2015-02-04 11:51:39 -08:00
Leonardo de Moura
8912c759dd fix(frontends/lean/parse_rewrite_tactic): corner case "rewrite ?(t)" 
The token '?(' is used to represent inaccessible terms in recursive
equations. In the rewriter tactic, we want "rewrite ?(t)" to be parsed
as "? (t)".
 2015-02-04 11:51:39 -08:00
Leonardo de Moura
991d29b7f6 fix(frontends/lean/parse_rewrite_tactic): bugs in rewrite tactic parser 2015-02-04 11:51:39 -08:00
Leonardo de Moura
d6a7ec4621 chore(library/tactic/rewrite_tactic): fix style 2015-02-04 11:51:39 -08:00
Leonardo de Moura
b4dd2cc729 refactor(library/tactic/rewrite_tactic): more general rewrite step 
The rule can be an arbitrary expression.
Allow user to provide a pattern that restricts the application of the rule.
 2015-02-04 11:51:39 -08:00
Leonardo de Moura
461fd45efc feat(frontends/lean): allow a different location for each rewrite element 2015-02-04 11:51:39 -08:00
Leonardo de Moura
c845e44777 feat(frontends/lean): parse rewrite tactic 2015-02-04 11:51:39 -08:00
Leonardo de Moura
180cda304e feat(library/tactic): add rewrite tactic skeleton 
The tactic has not been implemented yet, but this commit adds all the
support for storing arguments, serializing and deserializing them.
 2015-02-04 11:51:39 -08:00
Leonardo de Moura
87bcec2e5e feat(frontends/lean): parse tactic location (i.e., scope of application) 2015-02-04 11:51:39 -08:00
Leonardo de Moura
8a78adc9af feat(library/tactic): add auxiliary object "location" 
This object will used to specify the scope of application of tactics
 2015-02-04 11:51:39 -08:00
Leonardo de Moura
2a6ccb252e test(tests/lean/extra): add regression tests for issue #422 2015-02-04 10:55:03 -08:00
Leonardo de Moura
0cea63651d fix(frontends/lean): store line/col information at snapshots, save snapshot before 'end' scope, and before "closing" open namespaces 
closes #422
 2015-02-04 10:40:36 -08:00
Leonardo de Moura
420da8fd3f feat(library/projection): store bit saying whether a projection is for a class or not. 2015-02-04 08:54:20 -08:00
Leonardo de Moura
1ee47dc063 feat(frontends/lean/server): suppress projections from autocompletion 
closes #424
 2015-02-04 07:18:47 -08:00
Leonardo de Moura
c92f3bec65 refactor(library/definitional/projection): move projection "database" to library/projection 2015-02-04 07:18:43 -08:00
Leonardo de Moura
0e06f4aedc feat(library/match): extend match_plugin interface 2015-02-03 18:10:38 -08:00
Leonardo de Moura
44e575c895 feat(library/match): improve match_app_core 2015-02-03 17:37:22 -08:00
Leonardo de Moura
790fd9c24b chore(library/match): remove unused procedure 2015-02-03 15:20:26 -08:00
Leonardo de Moura
f79f43c702 refactor(library/match): use "special" meta-variables instead of free variables to represent placholders in the higher-order matcher 2015-02-03 15:15:04 -08:00
Leonardo de Moura
fc6d9878c9 refactor(kernel): add expr_cache 
It is the old instantiate_metavars_cache.
 2015-02-03 14:59:55 -08:00
Jeremy Avigad
dc7b432482 feat(src/emacs/README.md): tell user that packages will be installed automatically. Closes #423. 2015-02-03 13:50:59 -08:00
Jeremy Avigad
875869fdbc fix(src/emacs/README.md): make minor grammatical corrections 2015-02-03 13:50:59 -08:00
Leonardo de Moura
45e62031e2 fix(library/match): bug in matcher 2015-02-03 13:46:19 -08:00
Leonardo de Moura
9d1e312c12 test(tests/lean/extra): add extra tests for 'print' command 2015-02-01 20:20:26 -08:00
Leonardo de Moura
7d9d89bae6 test(tests/lean/extra): add test for saving recursive equation pre-terms 2015-02-01 19:49:14 -08:00
Leonardo de Moura
15716c1471 feat(frontends/lean/calc_proof_elaborator): reject proofs with metavariables in the calc-assistant 2015-02-01 11:11:27 -08:00
Leonardo de Moura
4c7a17cc4a refactor(library/tactic/class_instance_synth): move has_expr_metavar_relaxed to util 2015-02-01 10:59:27 -08:00
Leonardo de Moura
c311e0aba6 chore(library/tactic/inversion_tactic): cleanup 2015-02-01 10:47:32 -08:00
Leonardo de Moura
143143e94c fix(library/tactic/inversion_tactic): missing normalization step in the inversion_tactic 2015-02-01 10:38:30 -08:00
Leonardo de Moura
d52af105d7 feat(frontends/lean/decl_cmds): allow many constants to be set in the same attribute command 2015-01-31 23:55:14 -08:00
Leonardo de Moura
855050e623 feat(frontends/lean/calc_proof_elaborator): try conservative alternatives first 2015-01-31 21:29:34 -08:00
Leonardo de Moura
27741e4fd7 chore(CMakeLists.txt): move Lean logo to make sure we can test leanemacs without installing Lean 2015-01-31 17:38:49 -08:00
Leonardo de Moura
099111db32 fix(CMakeLists.txt): option ==> set 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2015-01-30 14:49:20 -08:00
Leonardo de Moura
fbb543fdcf feat(CMakeLists.txt): add alternative image formats 2015-01-30 14:26:46 -08:00
Leonardo de Moura
6456c2b89a feat(CMakeLists.txt): add leanemacs.bat for Windows 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2015-01-30 14:16:57 -08:00
Soonho Kong
7bed63a03e doc(emacs/README.md): fix typos 
[skip ci]
 2015-01-30 16:10:21 -05:00
Leonardo de Moura
c8cb9aa3d2 fix(emacs/load-lean): typo 2015-01-30 13:05:30 -08:00
Leonardo de Moura
2c926478dd feat(bin): add leanemacs startup script 2015-01-30 13:05:30 -08:00
Leonardo de Moura
9910547913 feat(emacs): add script for loading lean mode and its dependencies 2015-01-30 13:05:30 -08:00
Leonardo de Moura
a57251913a feat(emacs): assume lua-mode and mmm-mode are available 2015-01-30 13:05:30 -08:00
Leonardo de Moura
d0ce4cf62f fix(CMakeLists.txt): path to ninja 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2015-01-30 10:37:49 -08:00
Leonardo de Moura
a44fec6eb4 fix(CMakeLists.txt): path to ninja 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2015-01-30 10:32:35 -08:00
Leonardo de Moura
1ee52a3ddc feat(CMakeLists.txt): include ninja in Windows binary distribution package 
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
 2015-01-30 09:59:55 -08:00
Leonardo de Moura
7c59c959db fix(tests/lean/interactive): do not compare output of trace using non-deterministic commands such as "WAIT ms" 2015-01-30 09:52:42 -08:00
Soonho Kong
d98f04fd3a chore(emacs/README.md): add numbering on configuration 
[skip ci]
 2015-01-30 03:08:11 -05:00
Soonho Kong
04249a292c feat(emacs/README.md): add per-installation-method configurations 2015-01-30 03:05:35 -05:00
Soonho Kong
ce0aed12ec fix(emacs/Cask): add GNU package repository 
Related issue #410
 2015-01-30 02:52:55 -05:00
Soonho Kong
d69505a092 doc(emacs/README.md): add GNU package repository 
flycheck uses let-alist package which is in GNU repository. @awody reported a problem and I hope that this can help (I'll test it later).

Reference: https://github.com/flycheck/flycheck/issues/551

Related issue: #410
 2015-01-30 02:52:05 -05:00
Leonardo de Moura
f04e462bf3 test(tests/lean/interactive): add more tests for lean server 2015-01-29 16:30:07 -08:00
Leonardo de Moura
e9e1f86b7f fix(library/app_builder): many bugs, add use_cache option, add tests 2015-01-29 15:30:31 -08:00
Leonardo de Moura
e6f022e3f2 fix(library/match): index out of bounds 2015-01-29 14:41:38 -08:00
Leonardo de Moura
b5d1f4e54c feat(library/match): add low-level match API 2015-01-29 14:09:09 -08:00
Leonardo de Moura
f587cc3e1d feat(library/app_builder): expose app_builder API in Lua 2015-01-29 11:38:56 -08:00
Leonardo de Moura
5efd91e435 fix(library/app_builder): missing initialization 2015-01-29 11:38:28 -08:00
Leonardo de Moura
5bb2a41c64 feat(library/reducible): expose Lua API for reducible hints 2015-01-29 10:37:15 -08:00
Leonardo de Moura
4cf2dcaa7e feat(library/app_builder): add helper class for creating applications efficiently using type inference 
The idea is to use this class in the simplifier.
For example, we will use to create: symmetry, reflexivity, transitivity
and congruence proof steps.
 2015-01-28 18:40:21 -08:00
Leonardo de Moura
4e08cc0659 feat(library/match): add flag for tracking whether matcher assigned anything 2015-01-28 18:39:50 -08:00
Leonardo de Moura
dbc8e9e13a refactor(*): add method get_num_univ_params 2015-01-28 17:22:18 -08:00
Leonardo de Moura
5aaade47d8 feat(library/match): add new API 2015-01-28 16:42:42 -08:00
Leonardo de Moura
e4b5e07498 fix(frontends/lean/elaborator): apply substitution before compiling pre-tactics into tactics 
closes #415
 2015-01-28 13:32:56 -08:00
Leonardo de Moura
1119a8018a fix(util/buffer): destructor was not being invoked at erase and erase_elem 
This bug was producing a weird memory leak in the definition package.
The methods erase and erase_elem are not used very often. This is why
this bug was never detected.
 2015-01-27 18:48:02 -08:00
Leonardo de Moura
ad4c7c20f9 fix(kernel/inductive/inductive): fix assertion violation when K is applied to type incorrect term 2015-01-27 11:22:14 -08:00
Leonardo de Moura
1dbe4b8fb7 feat(kernel/extension_context): add auxiliary method is_def_eq 2015-01-27 11:17:54 -08:00
Leonardo de Moura
2a5658ebe2 fix(frontends/lean/elaborator_context): memory leak 2015-01-26 16:08:51 -08:00
Leonardo de Moura
e2c41fca75 feat(frontends/lean): modify syntax for local notation 
The idea is to make it uniform with the syntax for defining local
attributes.
 2015-01-26 11:51:17 -08:00
Leonardo de Moura
b4d6f6e3ed feat(frontends/lean): 'attribute' command is persistent by default 2015-01-26 11:51:17 -08:00
Leonardo de Moura
a1eeb0a6a1 fix(library/print): typo in is_used_name 
closes #408
 2015-01-25 08:58:08 -08:00
Leonardo de Moura
4f2e0c6d7f refactor(frontends/lean): add 'attribute' command 
The new command provides a uniform way to set declaration attributes.
It replaces the commands: class, instance, coercion, multiple_instances,
reducible, irreducible
 2015-01-24 20:23:21 -08:00
Leonardo de Moura
b5c4e603db feat(frontends/lean): allow parameters to be used in sections 
Restriction:
- coercions and notations cannot be defined in parametric sections

closes #401
 2015-01-23 17:42:19 -08:00
Leonardo de Moura
27f6bfd3f0 refactor(*): add file constants.txt with all constants used by the Lean binary 2015-01-23 16:50:32 -08:00
Favonia
2d69444da5 fix(cmake/Modules/cpplint.py): python3 compatible without six 2015-01-22 13:05:56 -08:00
Favonia
c1bfafd2a7 style(cmake/Modules/cpplint.py) 2015-01-22 13:05:56 -08:00
Favonia
a2f30322a9 fix(cmake/Modules/cpplint.py): delete ending colon 
Delete the erroneous ending colon.
 2015-01-22 13:05:56 -08:00
Favonia
51c771f334 revert(cmake/Modules/cpplint.py): roll back to python2 version 
This reverts commit 65cc4d3c08.
 2015-01-22 13:05:42 -08:00
Leonardo de Moura
880faf89e0 feat(frontends/lean/structure_cmd): add implicit_infer_kind annotation to structure command 
closes #354
 2015-01-21 18:12:29 -08:00
Leonardo de Moura
a53098385c refactor(frontends/lean/type_util): move infer_implicit_params to library 2015-01-21 17:22:41 -08:00
Soonho Kong
65cc4d3c08 fix(cmake/Modules/cpplint.py): roll back to python2 version 2015-01-21 19:26:38 -05:00
Leonardo de Moura
12674114a4 feat(shell): set default behavior to "trusted" 
closes #402
 2015-01-21 16:25:09 -08:00