lean2/tests/lua/ind1.lua
Leonardo de Moura 28b70b4e04 feat(kernel/inductive): use nondependent elimination when the datatype is in Bool/Prop
Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
2014-05-18 15:39:48 -07:00

102 lines
4.4 KiB
Lua

local env = empty_environment()
local l = mk_param_univ("l")
local A = Const("A")
local U_l = mk_sort(l)
local U_l1 = mk_sort(max_univ(l, 1)) -- Make sure U_l1 is not Bool/Prop
local list_l = Const("list", {l}) -- list.{l}
local Nat = Const("nat")
local vec_l = Const("vec", {l}) -- vec.{l}
local zero = Const("zero")
local succ = Const("succ")
local forest_l = Const("forest", {l})
local tree_l = Const("tree", {l})
local n = Const("n")
env = env:add_global_level("u")
env = env:add_global_level("v")
local u = global_univ("u")
local v = global_univ("v")
function display_type(env, t)
print(tostring(t) .. " : " .. tostring(type_checker(env):infer(t)))
end
env = add_inductive(env,
"nat", Type,
"zero", Nat,
"succ", mk_arrow(Nat, Nat))
-- In the following inductive datatype, {l} is the list of universe level parameters.
-- 1 is the number of parameters.
-- The Boolean true in {A, U_l, true} is marking that this argument is implicit.
env = add_inductive(env,
"list", {l}, 1, Pi(A, U_l, U_l1),
"nil", Pi({{A, U_l, true}}, list_l(A)),
"cons", Pi({{A, U_l, true}}, mk_arrow(A, list_l(A), list_l(A))))
env = add_inductive(env,
"vec", {l}, 1,
mk_arrow(U_l, Nat, U_l1),
"vnil", Pi({{A, U_l, true}}, vec_l(A, zero)),
"vcons", Pi({{A, U_l, true}, {n, Nat, true}}, mk_arrow(A, vec_l(A, n), vec_l(A, succ(n)))))
local And = Const("and")
local Or = Const("or")
local B = Const("B")
-- Datatype without introduction rules (aka constructors). It is a uninhabited type.
env = add_inductive(env, "false", Bool)
-- Datatype with a single constructor.
env = add_inductive(env, "true", Bool, "trivial", Const("true"))
env = add_inductive(env,
"and", 2, Pi({{A, Bool}, {B, Bool}}, Bool),
"and_intro", Pi({{A, Bool, true}, {B, Bool, true}}, mk_arrow(A, B, And(A, B))))
env = add_inductive(env,
"or", 2, Pi({{A, Bool}, {B, Bool}}, Bool),
"or_intro_left", Pi({{A, Bool, true}, {B, Bool, true}}, mk_arrow(A, Or(A, B))),
"or_intro_right", Pi({{A, Bool, true}, {B, Bool, true}}, mk_arrow(B, Or(A, B))))
local P = Const("P")
local a = Const("a")
local exists_l = Const("exists", {l})
env = add_inductive(env,
"exists", {l}, 2, Pi({{A, U_l}, {P, mk_arrow(A, Bool)}}, Bool),
"exists_intro", Pi({{A, U_l, true}, {P, mk_arrow(A, Bool), true}, {a, A}}, mk_arrow(P(a), exists_l(A, P))))
env = add_inductive(env, {l}, 1,
{"tree", Pi(A, U_l, U_l1),
"node", Pi({{A, U_l, true}}, mk_arrow(A, forest_l(A), tree_l(A)))
},
{"forest", Pi(A, U_l, U_l1),
"emptyf", Pi({{A, U_l, true}}, forest_l(A)),
"consf", Pi({{A, U_l, true}}, mk_arrow(tree_l(A), forest_l(A), forest_l(A)))})
local tc = type_checker(env)
display_type(env, Const("forest", {mk_level_zero()}))
display_type(env, Const("vcons", {mk_level_zero()}))
display_type(env, Const("consf", {mk_level_zero()}))
display_type(env, Const("forest_rec", {v, u}))
display_type(env, Const("nat_rec", {v}))
display_type(env, Const("or_rec"))
local Even = Const("Even")
local Odd = Const("Odd")
local b = Const("b")
env = add_inductive(env, {},
{"Even", mk_arrow(Nat, Bool),
"zero_is_even", Even(zero),
"succ_odd", Pi(b, Nat, mk_arrow(Odd(b), Even(succ(b))))},
{"Odd", mk_arrow(Nat, Bool),
"succ_even", Pi(b, Nat, mk_arrow(Even(b), Odd(succ(b))))})
local flist_l = Const("flist", {l})
env = add_inductive(env,
"flist", {l}, 1, mk_arrow(U_l, U_l1),
"fnil", Pi({{A, U_l, true}}, flist_l(A)),
"fcons", Pi({{A, U_l, true}}, mk_arrow(A, mk_arrow(Nat, flist_l(A)), flist_l(A))))
local eq_l = Const("eq", {l})
env = add_inductive(env,
"eq", {l}, 2, Pi({{A, U_l}, {a, A}, {b, A}}, Bool),
"refl", Pi({{A, U_l}, {a, A}}, eq_l(A, a, a)))
display_type(env, Const("eq_rec", {v, u}))
display_type(env, Const("exists_rec", {v, u}))
display_type(env, Const("list_rec", {v, u}))
display_type(env, Const("Even_rec"))
display_type(env, Const("Odd_rec"))