Leonardo de Moura
bed0d6df6b
fix(frontends/lean/elaborator): inaccessible over coercion
2015-03-13 23:04:45 -07:00
Leonardo de Moura
47a350d888
fix(library/tactic/inversion_tactic): missing condition for applying optimization
2015-03-12 09:11:36 -07:00
Leonardo de Moura
4c6b0dc0e5
fix(library/tactic/expr_to_tactic): tactic_expr_to_id did not take as_atomic annotation into account
...
fixes #466
2015-03-11 08:49:59 -07:00
Leonardo de Moura
4904f7657f
test(tests/lean/run): add definition package tests
2015-03-09 08:42:21 -07:00
Leonardo de Moura
f966634910
feat(frontends/lean): nested dependent pattern matching
2015-03-06 19:18:08 -08:00
Leonardo de Moura
14ca2d407d
test(tests/lean/run): add match-with nested in tactic test
2015-03-06 17:47:01 -08:00
Leonardo de Moura
1490bdad49
feat(frontends/lean): add version of 'exact' tactic (sexact) that enforces goal type during term elaboration
2015-03-06 17:34:45 -08:00
Leonardo de Moura
bd8c4315f1
feat(frontends/lean): allow 'match-with' to be used in tactics without prefixing it with 'exact'
2015-03-06 15:49:31 -08:00
Leonardo de Moura
4edd7b9099
fix(library/definitional/equations): allow a function to be the result of a match-with term or recursive definition
2015-03-06 15:08:52 -08:00
Leonardo de Moura
f24d9e84fe
feat(frontends/lean): add option 'max_memory'
...
Default value is 512Mb
2015-03-06 13:56:20 -08:00
Leonardo de Moura
3b721fe675
feat(frontends/lean): add missing 'help' command
2015-03-06 13:56:20 -08:00
Leonardo de Moura
daf36803c4
fix(frontends/lean/builtin_exprs): bug in 'using' construct
2015-03-06 13:56:20 -08:00
Leonardo de Moura
368f9d347e
refactor(frontends/lean): approach used to parse tactics
...
The previous approach was too fragile
TODO: we should add separate parsing tables for tactics
2015-03-05 18:11:21 -08:00
Leonardo de Moura
28487ede3b
feat(frontends/lean/decl_cmds): allow 'empty' set of pattern matching equations
2015-03-05 14:37:29 -08:00
Leonardo de Moura
b73a931c70
fix(frontends/lean/elaborator): missing case 'no-equation' annotation
2015-03-05 14:37:29 -08:00
Leonardo de Moura
039afb4578
feat(frontends/lean): treat "proof t qed" as alias for "by exact t"
2015-03-05 11:12:39 -08:00
Leonardo de Moura
abd238aef0
feat(*): add [quasireducible] attribute
2015-03-04 22:12:49 -08:00
Leonardo de Moura
fa79b214b8
fix(frontends/lean): allow 'attribute <id> [priority ...]'
2015-03-03 16:17:32 -08:00
Leonardo de Moura
3b73e100dc
test(tests/lean/run): add [priority] test using num.sub
2015-03-03 15:59:17 -08:00
Leonardo de Moura
efd096e85c
feat(library/init/num): define sub and le for binary numerals
2015-03-03 15:55:16 -08:00
Leonardo de Moura
c772d7bf84
fix(frontends/lean/elaborator): unassigned metavariable when using nested begin-end blocks
...
Closes #454
2015-02-28 09:03:56 -08:00
Leonardo de Moura
cf56935b01
feat(frontends/lean): improve support for user defined tactics
2015-02-27 16:58:25 -08:00
Leonardo de Moura
5b736a2268
feat(frontends/lean): add support for empty match-with expressions
2015-02-26 16:36:15 -08:00
Leonardo de Moura
68110faa4d
feat(frontends/lean/inductive_cmd): allow '|' in inductive datatype declarations
2015-02-25 17:00:10 -08:00
Leonardo de Moura
5ca52d81ec
feat(frontends/lean): ML-like notation for match and recursive equations
2015-02-25 16:20:44 -08:00
Leonardo de Moura
3c24461e51
refactor(*): modify '|' binding power, use 'abs a' instead of '|a|', and '(a | b)' instead of 'a | b'
2015-02-25 15:18:21 -08:00
Leonardo de Moura
c04c610b7b
feat(frontends/lean): add 'assert H : A, ...' as notation for 'have H [visible] : A, ...'
2015-02-25 14:30:42 -08:00
Jeremy Avigad
e555531eb6
feat(library/data/int/div): start on div for integers
2015-02-25 14:05:07 -08:00
Leonardo de Moura
96b54a8007
feat(frontends/lean/builtin_exprs): add 'have' notation in 'begin-end' blocks
...
It is notation for the assert tactic.
2015-02-25 14:04:17 -08:00
Leonardo de Moura
909ebfc5f1
feat(frontends/lean/elaborator): try coercions after each overload
...
We try only the easy cases since the more general case is too expensive.
closes #444
2015-02-24 17:41:20 -08:00
Leonardo de Moura
34c36648bb
fix(frontends/lean/decl_cmds): constants command
...
closes #445
2015-02-24 16:27:13 -08:00
Leonardo de Moura
42289d4334
feat(library/tactic/class_instance_synth): create class instance synthesis subproblems only for arguments marked with the []
binder annotation
2015-02-24 16:12:39 -08:00
Leonardo de Moura
1cd44e894b
feat(library/tactic/class_instance_synth): conservative class-instance resolution: expand only definitions marked as reducible
...
closes #442
2015-02-24 16:12:35 -08:00
Leonardo de Moura
1ff6446a63
feat(frontends/lean): nested begin-end blocks
2015-02-24 11:59:27 -08:00
Leonardo de Moura
dc2ac92846
fix(library/definitional/equations): use whnf on recursive definition arguments
...
The idea is to expose "hidden" datatypes.
2015-02-23 22:27:30 -08:00
Leonardo de Moura
7adecaf494
fix(frontends/lean/structure_cmd): include context/section parameteres/variables that are used in explicit structure parameters
2015-02-23 15:28:43 -08:00
Leonardo de Moura
7d35d18cad
fix(library/tactic/rewrite_tactic): bug when matching terms that expanded into projections
2015-02-22 18:23:10 -08:00
Leonardo de Moura
33e562a7ce
fix(frontends/lean/structure_cmd): effect of "include" command in the structure command
...
closes #438
2015-02-19 22:44:51 -08:00
Leonardo de Moura
4248ad644d
fix(frontends/lean): priority expressions parser
2015-02-14 12:26:06 -08:00
Leonardo de Moura
8ffadce4ab
feat(frontends/lean): add "premise" and "premises" command
...
It is just an alternative notation for "variable" and "variables"
closes #429
2015-02-11 18:46:03 -08:00
Leonardo de Moura
a35cce38b3
feat(frontends/lean): new semantics for "protected" declarations
...
closes #426
2015-02-11 14:09:25 -08:00
Leonardo de Moura
1832fb6f54
feat(*): uniform metaclass names, metaclass validation at 'open' command
2015-02-11 10:35:04 -08:00
Leonardo de Moura
9d1cd073c5
feat(frontends/lean): add 'print metaclasses' command
2015-02-11 10:13:20 -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
1e8a975daa
feat(frontends/lean): extend parser: rewrite "fold" step
2015-02-06 15:22:34 -08:00
Leonardo de Moura
04f8278c90
test(tests/lean/run): add rewrite tactic test
2015-02-06 14:14:42 -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
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
78bde6c9e6
test(tests/lean/run): add more rewrite tactic tests
2015-02-06 12:57:42 -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
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
e097977bac
test(tests/lean/run): add more rewrite tactic tests
2015-02-05 14:09:07 -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
808521223b
feat(library/tactic/rewrite_tactic): support constant unfolding in rewrite tactic
2015-02-05 12:58:30 -08:00
Leonardo de Moura
1b73764ad3
fix(tests/lean/run/elim2): adjust test to reflect recent changes
2015-02-05 10:54:00 -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
dfad24e3f5
feat(frontends/lean): polish rewrite tactic notation
2015-02-05 10:15:58 -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
d0171ffe7a
test(tests/lean/run): add more rewrite tactic examples
2015-02-04 19:19:46 -08:00
Leonardo de Moura
0c8eaa38c8
test(tests/lean/run): add basic rewriter test
2015-02-04 15:30:18 -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
3f37c0e739
test(tests/lean/run): add 'export' command test
2015-02-01 19:57:26 -08:00
Leonardo de Moura
6cd4972a84
fix(tests/lean): adjust tests to reflect changes in the standard library
2015-02-01 11:36:38 -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
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
e75828b756
test(tests/lean/interactive): add tests for options structure.eta_thm and structure.proj_mk_thm
2015-01-29 16:52:23 -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
5bb2a41c64
feat(library/reducible): expose Lua API for reducible hints
2015-01-29 10:37:15 -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
94519b48b1
fix(tests/lean): adjust tests to reflect changes in the standard library
2015-01-27 11:37:17 -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
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
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
002050fa97
feat(frontends/lean): increase binding power of ! and @
...
Remark: I did not add the constant "app".
Reason: It would break the standard library in many places.
Moreover, the current "max" is not just the binding power of
application, but also the binding power of identifiers, (, [, ...
It would be weird to call it "app"
closes #388
2015-01-19 18:40:33 -08:00
Leonardo de Moura
6fd0d452d3
test(tests/lean/run): adjust tests to reflect recent changes
2015-01-19 18:00:14 -08:00
Leonardo de Moura
edcc92d9c7
feat(frontends/lean): remove 'using' from structure instance command
2015-01-17 09:38:10 -08:00
Leonardo de Moura
fed96c9e0b
test(tests/lean/run): add structure instance example
2015-01-17 09:27:15 -08:00
Leonardo de Moura
f9d7480f5c
feat(frontends/lean): notation for creating structure instances
2015-01-16 17:14:30 -08:00
Leonardo de Moura
bfd679d52d
feat(frontends/lean/structure_cmd): allow user to reference parent structures when defining new fields
...
See new test for an example.
closes #371
2015-01-16 13:04:48 -08:00
Leonardo de Moura
91366c989d
test(tests/lean/run/finbug): add problematic definition test
2015-01-13 18:49:37 -08:00
Leonardo de Moura
e5a8c67d22
fix(library/definitional/equations): assertion violation
2015-01-13 11:57:14 -08:00
Leonardo de Moura
75d7e4ab9e
feat(frontends/lean): add 'end' token to match expressions
2015-01-10 12:35:29 -08:00
Leonardo de Moura
d6eccd7c18
test(tests/lean/run): add match test
2015-01-10 10:43:24 -08:00
Leonardo de Moura
b172229a72
feat(frontends/lean): add 'match' expressions
...
We reuse the equations infrastructure to compile them.
2015-01-10 10:11:13 -08:00
Leonardo de Moura
6df9ffe5f6
fix(frontends/lean/elaborator): solve placeholders before invoking equantions compiler
2015-01-10 09:18:27 -08:00
Leonardo de Moura
2e4a2451e6
refactor(library/reducible): simplify reducible/irreducible semantics
2015-01-08 18:52:18 -08:00
Leonardo de Moura
0ffb7c080f
fix(tests/lean/run/inv_bug2): adjust test to reflect changes at data.vector
2015-01-08 12:11:52 -08:00
Leonardo de Moura
4e49e73585
refactor(library/init/logic): add inhabited related functions, rename inhabited.default to default
2015-01-07 18:45:58 -08:00
Leonardo de Moura
1fab144aa7
refactor(library/init/nat): rename constants
...
closes #387
2015-01-07 18:26:51 -08:00
Jeremy Avigad
50f03c5a09
refactor(library/data/nat/order): make nat order an instance of linear_ordered_semigroup, rename various theorems
2015-01-07 18:18:28 -08:00
Leonardo de Moura
a3a6697f44
feat(library/definitional/equations): mutually recursive functions for mutually recursive datatypes
2015-01-06 14:07:17 -08:00
Leonardo de Moura
fb1cb3c623
test(tests/lean/run): define tree_list length function using recursive equations
...
tree_list is part of a mutually inductive datatype.
2015-01-06 11:57:34 -08:00
Leonardo de Moura
6451cad38d
test(tests/lean/run): define list head using recursive equations
2015-01-05 19:50:34 -08:00
Leonardo de Moura
3325d791de
fix(library/definitional/equations): bug in recursive application elimination
2015-01-05 17:17:14 -08:00
Leonardo de Moura
cbae6a2ca0
test(tests/lean/run): define list filter function using recursive equations
2015-01-05 17:05:01 -08:00
Leonardo de Moura
a24a7f7fa1
test(tests/lean/run) define vector last and unzip functions using recursive equations
2015-01-05 17:04:55 -08:00
Leonardo de Moura
eedc31f7e9
fix(library/definitional/equations): bug in "complete" transition
2015-01-05 16:27:29 -08:00
Leonardo de Moura
3889b60152
feat(library/definitional/equations): allow inductive datatype parameters in recursive equations
2015-01-05 15:56:28 -08:00
Leonardo de Moura
d8f3bcec67
feat(library/init/logic): add 'arbitrary'
...
It is identical to default, but it is opaque.
That is, when we use 'arbitrary A', we cannot rely on the particular
value selected.
2015-01-05 13:27:09 -08:00
Leonardo de Moura
0d84943d52
test(tests/lean/run): show that nat has decidable equality using recursive equations
2015-01-05 12:41:18 -08:00
Leonardo de Moura
fd332e411d
test(tests/lean/run): add more overlapping patterns examples
2015-01-05 12:25:14 -08:00
Leonardo de Moura
b46c377aa2
feat(library/definitional/equations): add "complete" transition for overlapping patterns
2015-01-05 11:49:27 -08:00
Leonardo de Moura
fdef3e5407
feat(library/definitional/equations): add support for reflexive datatypes in the definitional package
2015-01-05 11:13:35 -08:00
Leonardo de Moura
5e228d92d2
fix(library/definitional/equations): missing case
2015-01-04 20:49:53 -08:00
Leonardo de Moura
f07475667b
test(tests/lean/run): define vector map using recursive equations
2015-01-04 19:56:50 -08:00
Leonardo de Moura
7ff03e2846
test(tests/lean/run): define vector diagonal using recursive equations
2015-01-04 17:58:35 -08:00
Leonardo de Moura
7488378445
test(tests/lean/run): define list append using recursive equations
2015-01-04 17:58:24 -08:00
Leonardo de Moura
7fca862fc3
test(tests/lean/run): define fibonacci using recursive equations
2015-01-04 17:47:18 -08:00
Leonardo de Moura
faf78ce3e6
feat(library/definitional/equations): brec_on compilation
2015-01-04 17:45:13 -08:00
Leonardo de Moura
92b6c06a21
test(tests/lean/run): add basic pattern matching compilation test
2015-01-02 22:22:20 -08:00
Leonardo de Moura
c66826787a
test(tests/lean/run): add basic pattern matching compilation test
2015-01-02 22:07:31 -08:00
Jeremy Avigad
1eea75b6fc
fix(library/data/nat/div,tests/lean/run/ppbeta): make decidable for dvd transparent, name change in ppbeta
2014-12-26 16:44:43 -05:00
Jeremy Avigad
25394dddb7
refactor(library): change mul.left_id to mul_one, and similarly for mul.right_id, add.left_id, add.right_id
2014-12-23 21:14:36 -05:00
Jeremy Avigad
486bc321ff
refactor(library/data/nat): rename theorems
2014-12-23 21:14:35 -05:00
Leonardo de Moura
d2958044fd
feat(frontends/lean): add multiple_instances command
...
After this commit, Lean "cuts" the search after the first instance is
computed. To obtain the previous behavior, we must use the new command
multiple_instances <class-name>
closes #370
2014-12-21 17:28:44 -08:00
Leonardo de Moura
1e2fc54f2f
refactor(library/init/sigma): rename sigma.dpair->sigma.mk, sigma.dpr1->sigma.pr1, sigma.dpr2->sigma.pr2
2014-12-19 18:23:08 -08:00
Leonardo de Moura
9eea32b076
refactor(library/init/datatypes): change implicit arguments of sum.inl and sum.inr
2014-12-19 18:07:13 -08:00
Leonardo de Moura
07d7ea2f4e
refactor(frontends/lean/placeholder_elaborator): reduce coupling between placeholder_elaborator and frontends/lean
2014-12-19 15:08:21 -08:00
Leonardo de Moura
1797e2846f
fix(tests/lean/run): replace "open [notation]" with "open [notations]"
2014-12-17 18:28:38 -08:00
Leonardo de Moura
43633085b9
fix(tests/lean): adjust tests to recent changes in the lean libraries
2014-12-16 13:28:43 -08:00
Leonardo de Moura
abe129aa4f
refactor(library): rename theorems "iff.flip_sign -> not_iff_not_of_iff" and "decidable_iff_equiv -> decidable_of_decidable_of_iff"
2014-12-15 19:17:51 -08:00
Leonardo de Moura
5cf8064269
refactor(library): rename exists_elim and exists_intro to exists.elim
...
and exists.intro
2014-12-15 19:07:38 -08:00
Jeremy Avigad
3e9a484851
refactor(library/logic/connectives): rename theorems
2014-12-15 15:05:44 -05:00
Leonardo de Moura
c6ebe9456e
feat(library/data/nat): add "bounded" quantifiers
...
Later, we will add support for arbitrary well-founded relations
2014-12-13 15:42:38 -08:00
Leonardo de Moura
f0b002d5a7
fix(library/aliases): aliases in sections and contexts
2014-12-13 14:57:15 -08:00
Leonardo de Moura
c291063f3a
fix(frontends/lean/structure_cmd): simplify structure names
2014-12-13 14:18:02 -08:00
Leonardo de Moura
477d79ae47
refactor(library/init): move more theorems to logic
2014-12-12 13:50:53 -08:00
Leonardo de Moura
d6c8e23b03
refactor(library/init/logic): move theorems to library/logic
2014-12-12 13:24:17 -08:00
Leonardo de Moura
b01cf73a91
feat(library/init/logic): add is_true and is_false
2014-12-11 18:14:03 -08:00
Leonardo de Moura
05f27b8f0e
feat(frontends/lean/structure): add option for controlling whether we automatically generate eta and projection-over-intro theorems for structures
...
It seems most of the time these theorems are not used at all.
They are just polluting the namespace.
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
2014-12-09 12:40:09 -08:00
Leonardo de Moura
e72c4977f0
feat(frontends/lean): nicer notation for dependent if-then-else
2014-12-04 11:13:09 -08:00
Leonardo de Moura
ebda057499
fix(library/tactic/intros_tactic): seg fault at intros tactic, fixes #366
2014-12-04 09:26:10 -08:00
Leonardo de Moura
1a813fc720
test(tests/lean/run/nested_rec.lean): add nested recursion example based on well-founded recursion package
2014-12-03 22:11:01 -08:00
Leonardo de Moura
811bc6a31f
feat(library/init/measurable): add 'measurable' type class
2014-12-03 18:54:24 -08:00
Leonardo de Moura
e5fc0f90b2
test(tests/lean/run): try different ways to pack mutually recursive datatypes
2014-12-03 15:28:44 -08:00
Leonardo de Moura
9ae96514e0
test(tests/lean/run): use 'cases' tactic
2014-12-03 15:28:22 -08:00
Leonardo de Moura
d10bb92a7d
feat(library/aliases): protected definitions in nested namespaces, closes #331
2014-12-03 14:25:02 -08:00
Leonardo de Moura
0443c1e70c
fix(frontends/lean): intro tactic + universe variables, fixes #362
2014-12-03 12:56:30 -08:00
Leonardo de Moura
fca97d5bb2
feat(library/definitional): add brec_on construction, closes #272
2014-12-03 10:39:32 -08:00
Leonardo de Moura
06f436840f
fix(library/unifier): postpone class-instance constraints whose type could not be inferred
2014-12-01 22:27:23 -08:00
Leonardo de Moura
e6672b958f
fix(library/tactic/inversion_tactic): add missing case
2014-12-01 19:11:44 -08:00
Leonardo de Moura
bc7ee2958f
fix(library/tactic/inversion_tactic): bug in mutually recursive case
2014-12-01 18:32:38 -08:00
Leonardo de Moura
6640fbf11b
feat(library/definitional/brec_on): simplify universe level constraints for non-reflexive recursive datatypes
2014-12-01 17:11:06 -08:00