lean4-htt/library/init/core.lean
Mario Carneiro 89e860ac8b doc(init/core): Document init_quotient in lean
This way people can search for "constant quot" and find it in the lean source. Plus the init_quotient command only occurs once, so this way people know what it means.
2017-07-20 01:36:28 -07:00

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/-
Copyright (c) 2014 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Leonardo de Moura
notation, basic datatypes and type classes
-/
prelude
notation `Prop` := Sort 0
notation f ` $ `:1 a:0 := f a
/- Logical operations and relations -/
reserve prefix `¬`:40
reserve prefix `~`:40
reserve infixr ` ∧ `:35
reserve infixr ` /\ `:35
reserve infixr ` \/ `:30
reserve infixr ` `:30
reserve infix ` <-> `:20
reserve infix ` ↔ `:20
reserve infix ` = `:50
reserve infix ` == `:50
reserve infix ` ≠ `:50
reserve infix ` ≈ `:50
reserve infix ` ~ `:50
reserve infix ` ≡ `:50
reserve infixl ` ⬝ `:75
reserve infixr ` ▸ `:75
reserve infixr ` ▹ `:75
/- types and type constructors -/
reserve infixr ` ⊕ `:30
reserve infixr ` × `:35
/- arithmetic operations -/
reserve infixl ` + `:65
reserve infixl ` - `:65
reserve infixl ` * `:70
reserve infixl ` / `:70
reserve infixl ` % `:70
reserve prefix `-`:100
reserve infix ` ^ `:80
reserve infixr ` ∘ `:90 -- input with \comp
reserve infix ` <= `:50
reserve infix ` ≤ `:50
reserve infix ` < `:50
reserve infix ` >= `:50
reserve infix ` ≥ `:50
reserve infix ` > `:50
/- boolean operations -/
reserve infixl ` && `:70
reserve infixl ` || `:65
/- set operations -/
reserve infix ` ∈ `:50
reserve infix ` ∉ `:50
reserve infixl ` ∩ `:70
reserve infixl ` `:65
reserve infix ` ⊆ `:50
reserve infix ` ⊇ `:50
reserve infix ` ⊂ `:50
reserve infix ` ⊃ `:50
reserve infix ` \ `:70
/- other symbols -/
reserve infix ` `:50
reserve infixl ` ++ `:65
reserve infixr ` :: `:67
reserve infixl `; `:1
universes u v w
/-- Gadget for optional parameter support. -/
@[reducible] def opt_param (α : Sort u) (default : α) : Sort u :=
α
/-- Gadget for marking output parameters in type classes. -/
@[reducible] def inout_param (α : Sort u) : Sort u := α
notation `inout`:1024 a:0 := inout_param a
inductive punit : Sort u
| star : punit
inductive unit : Type
| star : unit
/--
Gadget for defining thunks, thunk parameters have special treatment.
Example: given
def f (s : string) (t : thunk nat) : nat
an application
f "hello" 10
is converted into
f "hello" (λ _, 10)
-/
@[reducible] def thunk (α : Type u) : Type u :=
unit → α
inductive true : Prop
| intro : true
inductive false : Prop
inductive empty : Type
def not (a : Prop) := a → false
prefix `¬` := not
inductive eq {α : Sort u} (a : α) : α → Prop
| refl : eq a
/-
Initialize the quotient module, which effectively adds the following definitions:
constant quot {α : Sort u} (r : αα → Prop) : Sort u
constant quot.mk {α : Sort u} (r : αα → Prop) (a : α) : quot r
constant quot.lift {α : Sort u} {r : αα → Prop} {β : Sort v} (f : α → β) :
(∀ a b : α, r a b → eq (f a) (f b)) → quot r → β
constant quot.ind {α : Sort u} {r : αα → Prop} {β : quot r → Prop} :
(∀ a : α, β (quot.mk r a)) → ∀ q : quot r, β q
-/
init_quotient
inductive heq {α : Sort u} (a : α) : Π {β : Sort u}, β → Prop
| refl : heq a
structure prod (α : Type u) (β : Type v) :=
(fst : α) (snd : β)
/-- Similar to `prod`, but α and β can be propositions.
We use this type internally to automatically generate the brec_on recursor. -/
structure pprod (α : Sort u) (β : Sort v) :=
(fst : α) (snd : β)
inductive and (a b : Prop) : Prop
| intro : a → b → and
def and.elim_left {a b : Prop} (h : and a b) : a :=
and.rec (λ ha hb, ha) h
def and.left := @and.elim_left
def and.elim_right {a b : Prop} (h : and a b) : b :=
and.rec (λ ha hb, hb) h
def and.right := @and.elim_right
/- eq basic support -/
infix = := eq
attribute [refl] eq.refl
@[pattern] def rfl {α : Sort u} {a : α} : a = a := eq.refl a
@[elab_as_eliminator, subst]
lemma eq.subst {α : Sort u} {P : α → Prop} {a b : α} (h₁ : a = b) (h₂ : P a) : P b :=
eq.rec h₂ h₁
notation h1 ▸ h2 := eq.subst h1 h2
@[trans] lemma eq.trans {α : Sort u} {a b c : α} (h₁ : a = b) (h₂ : b = c) : a = c :=
h₂ ▸ h₁
@[symm] lemma eq.symm {α : Sort u} {a b : α} (h : a = b) : b = a :=
h ▸ rfl
infix == := heq
@[pattern] def heq.rfl {α : Sort u} {a : α} : a == a := heq.refl a
lemma eq_of_heq {α : Sort u} {a a' : α} (h : a == a') : a = a' :=
have ∀ (α' : Sort u) (a' : α') (h₁ : @heq α a α' a') (h₂ : α = α'), (eq.rec_on h₂ a : α') = a', from
λ (α' : Sort u) (a' : α') (h₁ : @heq α a α' a'), heq.rec_on h₁ (λ h₂ : α = α, rfl),
show (eq.rec_on (eq.refl α) a : α) = a', from
this α a' h (eq.refl α)
/- The following four lemmas could not be automatically generated when the
structures were declared, so we prove them manually here. -/
lemma prod.mk.inj {α : Type u} {β : Type v} {x₁ : α} {y₁ : β} {x₂ : α} {y₂ : β}
: (x₁, y₁) = (x₂, y₂) → and (x₁ = x₂) (y₁ = y₂) :=
λ h, prod.no_confusion h (λ h₁ h₂, ⟨h₁, h₂⟩)
lemma prod.mk.inj_arrow {α : Type u} {β : Type v} {x₁ : α} {y₁ : β} {x₂ : α} {y₂ : β}
: (x₁, y₁) = (x₂, y₂) → Π ⦃P : Sort w⦄, (x₁ = x₂ → y₁ = y₂ → P) → P :=
λ h₁ _ h₂, prod.no_confusion h₁ h₂
lemma pprod.mk.inj {α : Sort u} {β : Sort v} {x₁ : α} {y₁ : β} {x₂ : α} {y₂ : β}
: pprod.mk x₁ y₁ = pprod.mk x₂ y₂ → and (x₁ = x₂) (y₁ = y₂) :=
λ h, pprod.no_confusion h (λ h₁ h₂, ⟨h₁, h₂⟩)
lemma pprod.mk.inj_arrow {α : Type u} {β : Type v} {x₁ : α} {y₁ : β} {x₂ : α} {y₂ : β}
: (x₁, y₁) = (x₂, y₂) → Π ⦃P : Sort w⦄, (x₁ = x₂ → y₁ = y₂ → P) → P :=
λ h₁ _ h₂, prod.no_confusion h₁ h₂
inductive sum (α : Type u) (β : Type v)
| inl {} : α → sum
| inr {} : β → sum
inductive psum (α : Sort u) (β : Sort v)
| inl {} : α → psum
| inr {} : β → psum
inductive or (a b : Prop) : Prop
| inl {} : a → or
| inr {} : b → or
def or.intro_left {a : Prop} (b : Prop) (ha : a) : or a b :=
or.inl ha
def or.intro_right (a : Prop) {b : Prop} (hb : b) : or a b :=
or.inr hb
structure sigma {α : Type u} (β : α → Type v) :=
mk :: (fst : α) (snd : β fst)
structure psigma {α : Sort u} (β : α → Sort v) :=
mk :: (fst : α) (snd : β fst)
inductive bool : Type
| ff : bool
| tt : bool
/- Remark: subtype must take a Sort instead of Type because of the axiom strong_indefinite_description. -/
structure subtype {α : Sort u} (p : α → Prop) :=
(val : α) (property : p val)
attribute [pp_using_anonymous_constructor] sigma psigma subtype pprod
class inductive decidable (p : Prop)
| is_false : ¬p → decidable
| is_true : p → decidable
@[reducible]
def decidable_pred {α : Sort u} (r : α → Prop) :=
Π (a : α), decidable (r a)
@[reducible]
def decidable_rel {α : Sort u} (r : αα → Prop) :=
Π (a b : α), decidable (r a b)
@[reducible]
def decidable_eq (α : Sort u) :=
decidable_rel (@eq α)
inductive option (α : Type u)
| none {} : option
| some : α → option
export option (none some)
export bool (ff tt)
inductive list (T : Type u)
| nil {} : list
| cons : T → list → list
notation h :: t := list.cons h t
notation `[` l:(foldr `, ` (h t, list.cons h t) list.nil `]`) := l
inductive nat
| zero : nat
| succ : nat → nat
structure unification_constraint :=
{α : Type u} (lhs : α) (rhs : α)
infix ` ≟ `:50 := unification_constraint.mk
infix ` =?= `:50 := unification_constraint.mk
structure unification_hint :=
(pattern : unification_constraint)
(constraints : list unification_constraint)
/- Declare builtin and reserved notation -/
class has_zero (α : Type u) := (zero : α)
class has_one (α : Type u) := (one : α)
class has_add (α : Type u) := (add : ααα)
class has_mul (α : Type u) := (mul : ααα)
class has_inv (α : Type u) := (inv : αα)
class has_neg (α : Type u) := (neg : αα)
class has_sub (α : Type u) := (sub : ααα)
class has_div (α : Type u) := (div : ααα)
class has_dvd (α : Type u) := (dvd : αα → Prop)
class has_mod (α : Type u) := (mod : ααα)
class has_le (α : Type u) := (le : αα → Prop)
class has_lt (α : Type u) := (lt : αα → Prop)
class has_append (α : Type u) := (append : ααα)
class has_andthen (α : Type u) (β : Type v) (σ : inout Type w) := (andthen : α → β → σ)
class has_union (α : Type u) := (union : ααα)
class has_inter (α : Type u) := (inter : ααα)
class has_sdiff (α : Type u) := (sdiff : ααα)
class has_subset (α : Type u) := (subset : αα → Prop)
class has_ssubset (α : Type u) := (ssubset : αα → Prop)
/- Type classes has_emptyc and has_insert are
used to implement polymorphic notation for collections.
Example: {a, b, c}. -/
class has_emptyc (α : Type u) := (emptyc : α)
class has_insert (α : inout Type u) (γ : Type v) := (insert : αγγ)
/- Type class used to implement the notation { a ∈ c | p a } -/
class has_sep (α : inout Type u) (γ : Type v) :=
(sep : (α → Prop) → γγ)
/- Type class for set-like membership -/
class has_mem (α : inout Type u) (γ : Type v) := (mem : αγ → Prop)
def andthen {α : Type u} {β : Type v} {σ : Type w} [has_andthen α β σ] : α → β → σ :=
has_andthen.andthen σ
infix ∈ := has_mem.mem
notation a ∉ s := ¬ has_mem.mem a s
infix + := has_add.add
infix * := has_mul.mul
infix - := has_sub.sub
infix / := has_div.div
infix := has_dvd.dvd
infix % := has_mod.mod
prefix - := has_neg.neg
infix <= := has_le.le
infix ≤ := has_le.le
infix < := has_lt.lt
infix ++ := has_append.append
infix ; := andthen
notation `∅` := has_emptyc.emptyc _
infix := has_union.union
infix ∩ := has_inter.inter
infix ⊆ := has_subset.subset
infix ⊂ := has_ssubset.ssubset
infix \ := has_sdiff.sdiff
export has_append (append)
@[reducible] def ge {α : Type u} [has_le α] (a b : α) : Prop := has_le.le b a
@[reducible] def gt {α : Type u} [has_lt α] (a b : α) : Prop := has_lt.lt b a
infix >= := ge
infix ≥ := ge
infix > := gt
@[reducible] def superset {α : Type u} [has_subset α] (a b : α) : Prop := has_subset.subset b a
@[reducible] def ssuperset {α : Type u} [has_ssubset α] (a b : α) : Prop := has_ssubset.ssubset b a
infix ⊇ := superset
infix ⊃ := ssuperset
def bit0 {α : Type u} [s : has_add α] (a : α) : α := a + a
def bit1 {α : Type u} [s₁ : has_one α] [s₂ : has_add α] (a : α) : α := (bit0 a) + 1
attribute [pattern] has_zero.zero has_one.one bit0 bit1 has_add.add has_neg.neg
def insert {α : Type u} {γ : Type v} [has_insert α γ] : αγγ :=
has_insert.insert
/- The empty collection -/
def singleton {α : Type u} {γ : Type v} [has_emptyc γ] [has_insert α γ] (a : α) : γ :=
has_insert.insert a ∅
/- nat basic instances -/
namespace nat
protected def add : nat → nat → nat
| a zero := a
| a (succ b) := succ (add a b)
/- We mark the following definitions as pattern to make sure they can be used in recursive equations,
and reduced by the equation compiler. -/
attribute [pattern] nat.add nat.add._main
end nat
instance : has_zero nat := ⟨nat.zero⟩
instance : has_one nat := ⟨nat.succ (nat.zero)⟩
instance : has_add nat := ⟨nat.add⟩
def std.priority.default : nat := 1000
def std.priority.max : nat := 0xFFFFFFFF
namespace nat
protected def prio := std.priority.default + 100
end nat
/-
Global declarations of right binding strength
If a module reassigns these, it will be incompatible with other modules that adhere to these
conventions.
When hovering over a symbol, use "C-c C-k" to see how to input it.
-/
def std.prec.max : nat := 1024 -- the strength of application, identifiers, (, [, etc.
def std.prec.arrow : nat := 25
/-
The next def is "max + 10". It can be used e.g. for postfix operations that should
be stronger than application.
-/
def std.prec.max_plus : nat := std.prec.max + 10
reserve postfix `⁻¹`:std.prec.max_plus -- input with \sy or \-1 or \inv
postfix ⁻¹ := has_inv.inv
notation α × β := prod α β
-- notation for n-ary tuples
/- sizeof -/
class has_sizeof (α : Sort u) :=
(sizeof : α → nat)
def sizeof {α : Sort u} [s : has_sizeof α] : α → nat :=
has_sizeof.sizeof
/-
Declare sizeof instances and lemmas for types declared before has_sizeof.
From now on, the inductive compiler will automatically generate sizeof instances and lemmas.
-/
/- Every type `α` has a default has_sizeof instance that just returns 0 for every element of `α` -/
protected def default.sizeof (α : Sort u) : α → nat
| a := 0
instance default_has_sizeof (α : Sort u) : has_sizeof α :=
⟨default.sizeof α⟩
protected def nat.sizeof : nat → nat
| n := n
instance : has_sizeof nat :=
⟨nat.sizeof⟩
protected def prod.sizeof {α : Type u} {β : Type v} [has_sizeof α] [has_sizeof β] : (prod α β) → nat
| ⟨a, b⟩ := 1 + sizeof a + sizeof b
instance (α : Type u) (β : Type v) [has_sizeof α] [has_sizeof β] : has_sizeof (prod α β) :=
⟨prod.sizeof⟩
protected def sum.sizeof {α : Type u} {β : Type v} [has_sizeof α] [has_sizeof β] : (sum α β) → nat
| (sum.inl a) := 1 + sizeof a
| (sum.inr b) := 1 + sizeof b
instance (α : Type u) (β : Type v) [has_sizeof α] [has_sizeof β] : has_sizeof (sum α β) :=
⟨sum.sizeof⟩
protected def psum.sizeof {α : Type u} {β : Type v} [has_sizeof α] [has_sizeof β] : (psum α β) → nat
| (psum.inl a) := 1 + sizeof a
| (psum.inr b) := 1 + sizeof b
instance (α : Type u) (β : Type v) [has_sizeof α] [has_sizeof β] : has_sizeof (psum α β) :=
⟨psum.sizeof⟩
protected def sigma.sizeof {α : Type u} {β : α → Type v} [has_sizeof α] [∀ a, has_sizeof (β a)] : sigma β → nat
| ⟨a, b⟩ := 1 + sizeof a + sizeof b
instance (α : Type u) (β : α → Type v) [has_sizeof α] [∀ a, has_sizeof (β a)] : has_sizeof (sigma β) :=
⟨sigma.sizeof⟩
protected def psigma.sizeof {α : Type u} {β : α → Type v} [has_sizeof α] [∀ a, has_sizeof (β a)] : psigma β → nat
| ⟨a, b⟩ := 1 + sizeof a + sizeof b
instance (α : Type u) (β : α → Type v) [has_sizeof α] [∀ a, has_sizeof (β a)] : has_sizeof (psigma β) :=
⟨psigma.sizeof⟩
protected def unit.sizeof : unit → nat
| u := 1
instance : has_sizeof unit := ⟨unit.sizeof⟩
protected def punit.sizeof : punit → nat
| u := 1
instance : has_sizeof punit := ⟨punit.sizeof⟩
protected def bool.sizeof : bool → nat
| b := 1
instance : has_sizeof bool := ⟨bool.sizeof⟩
protected def option.sizeof {α : Type u} [has_sizeof α] : option α → nat
| none := 1
| (some a) := 1 + sizeof a
instance (α : Type u) [has_sizeof α] : has_sizeof (option α) :=
⟨option.sizeof⟩
protected def list.sizeof {α : Type u} [has_sizeof α] : list α → nat
| list.nil := 1
| (list.cons a l) := 1 + sizeof a + list.sizeof l
instance (α : Type u) [has_sizeof α] : has_sizeof (list α) :=
⟨list.sizeof⟩
protected def subtype.sizeof {α : Type u} [has_sizeof α] {p : α → Prop} : subtype p → nat
| ⟨a, _⟩ := sizeof a
instance {α : Type u} [has_sizeof α] (p : α → Prop) : has_sizeof (subtype p) :=
⟨subtype.sizeof⟩
lemma nat_add_zero (n : nat) : n + 0 = n := rfl
/- Combinator calculus -/
namespace combinator
universes u₁ u₂ u₃
def I {α : Type u₁} (a : α) := a
def K {α : Type u₁} {β : Type u₂} (a : α) (b : β) := a
def S {α : Type u₁} {β : Type u₂} {γ : Type u₃} (x : α → β → γ) (y : α → β) (z : α) := x z (y z)
end combinator
/- Basic unification hints -/
@[unify] def add_succ_defeq_succ_add_hint (x y z : nat) : unification_hint :=
{ pattern := x + nat.succ y ≟ nat.succ z,
constraints := [z ≟ x + y] }