Documentation

Init.Data.Bool

@[reducible, inline]
abbrev Bool.xor :
BoolBoolBool

Boolean exclusive or

Equations
instance Bool.instDecidableForallOfDecidablePred (p : BoolProp) [inst : DecidablePred p] :
Decidable (∀ (x : Bool), p x)
Equations
instance Bool.instDecidableExistsOfDecidablePred (p : BoolProp) [inst : DecidablePred p] :
Decidable (∃ (x : Bool), p x)
Equations
@[simp]
theorem Bool.default_bool :
default = false
instance Bool.instLE :
Equations
instance Bool.instLT :
Equations
instance Bool.instDecidableLe (x y : Bool) :
Equations
instance Bool.instDecidableLt (x y : Bool) :
Decidable (x < y)
Equations
Equations
Equations
theorem Bool.eq_iff_iff {a b : Bool} :
a = b (a = true b = true)
@[simp]
theorem Bool.decide_eq_true {b : Bool} [Decidable (b = true)] :
decide (b = true) = b
@[simp]
@[simp]
theorem Bool.eq_false_imp_eq_true_iff (a b : Bool) :
(a = falseb = true b = falsea = true) = True
@[simp]
theorem Bool.eq_true_imp_eq_false_iff (a b : Bool) :
(a = trueb = false b = truea = false) = True

and #

@[simp]
theorem Bool.and_self_left (a b : Bool) :
(a && (a && b)) = (a && b)
@[simp]
theorem Bool.and_self_right (a b : Bool) :
(a && b && b) = (a && b)
@[simp]
theorem Bool.not_and_self (x : Bool) :
(!x && x) = false
@[simp]
theorem Bool.and_not_self (x : Bool) :
(x && !x) = false
theorem Bool.and_comm (x y : Bool) :
(x && y) = (y && x)
instance Bool.instCommutativeAnd :
Std.Commutative fun (x1 x2 : Bool) => x1 && x2
Equations
theorem Bool.and_left_comm (x y z : Bool) :
(x && (y && z)) = (y && (x && z))
theorem Bool.and_right_comm (x y z : Bool) :
(x && y && z) = (x && z && y)
@[simp]
theorem Bool.and_iff_left_iff_imp {a b : Bool} :
(a && b) = a a = trueb = true
@[simp]
theorem Bool.and_iff_right_iff_imp {a b : Bool} :
(a && b) = b b = truea = true
@[simp]
theorem Bool.iff_self_and {a b : Bool} :
a = (a && b) a = trueb = true
@[simp]
theorem Bool.iff_and_self {a b : Bool} :
b = (a && b) b = truea = true
@[simp]
theorem Bool.not_and_iff_left_iff_imp {a b : Bool} :
(!a && b) = a (!a) = true (!b) = true
@[simp]
theorem Bool.and_not_iff_right_iff_imp {a b : Bool} :
(a && !b) = b (!a) = true (!b) = true
@[simp]
theorem Bool.iff_not_self_and {a b : Bool} :
a = (!a && b) (!a) = true (!b) = true
@[simp]
theorem Bool.iff_and_not_self {a b : Bool} :
b = (a && !b) (!a) = true (!b) = true

or #

@[simp]
theorem Bool.or_self_left (a b : Bool) :
(a || (a || b)) = (a || b)
@[simp]
theorem Bool.or_self_right (a b : Bool) :
(a || b || b) = (a || b)
@[simp]
theorem Bool.not_or_self (x : Bool) :
(!x || x) = true
@[simp]
theorem Bool.or_not_self (x : Bool) :
(x || !x) = true
@[simp]
theorem Bool.or_iff_left_iff_imp {a b : Bool} :
(a || b) = a b = truea = true
@[simp]
theorem Bool.or_iff_right_iff_imp {a b : Bool} :
(a || b) = b a = trueb = true
@[simp]
theorem Bool.iff_self_or {a b : Bool} :
a = (a || b) b = truea = true
@[simp]
theorem Bool.iff_or_self {a b : Bool} :
b = (a || b) a = trueb = true
@[simp]
theorem Bool.not_or_iff_left_iff_imp {a b : Bool} :
(!a || b) = a a = true b = true
@[simp]
theorem Bool.or_not_iff_right_iff_imp {a b : Bool} :
(a || !b) = b a = true b = true
@[simp]
theorem Bool.iff_not_self_or {a b : Bool} :
a = (!a || b) a = true b = true
@[simp]
theorem Bool.iff_or_not_self {a b : Bool} :
b = (a || !b) a = true b = true
theorem Bool.or_comm (x y : Bool) :
(x || y) = (y || x)
instance Bool.instCommutativeOr :
Std.Commutative fun (x1 x2 : Bool) => x1 || x2
Equations
theorem Bool.or_left_comm (x y z : Bool) :
(x || (y || z)) = (y || (x || z))
theorem Bool.or_right_comm (x y z : Bool) :
(x || y || z) = (x || z || y)

distributivity #

theorem Bool.and_or_distrib_left (x y z : Bool) :
(x && (y || z)) = (x && y || x && z)
theorem Bool.and_or_distrib_right (x y z : Bool) :
((x || y) && z) = (x && z || y && z)
theorem Bool.or_and_distrib_left (x y z : Bool) :
(x || y && z) = ((x || y) && (x || z))
theorem Bool.or_and_distrib_right (x y z : Bool) :
(x && y || z) = ((x || z) && (y || z))
theorem Bool.and_xor_distrib_left (x y z : Bool) :
(x && (y ^^ z)) = (x && y ^^ x && z)
theorem Bool.and_xor_distrib_right (x y z : Bool) :
((x ^^ y) && z) = (x && z ^^ y && z)
@[simp]
theorem Bool.not_and (x y : Bool) :
(!(x && y)) = (!x || !y)

De Morgan's law for boolean and

@[simp]
theorem Bool.not_or (x y : Bool) :
(!(x || y)) = (!x && !y)

De Morgan's law for boolean or

theorem Bool.and_eq_true_iff {x y : Bool} :
(x && y) = true x = true y = true
@[simp]
theorem Bool.and_eq_false_imp {x y : Bool} :
(x && y) = false x = truey = false
theorem Bool.or_eq_true_iff {x y : Bool} :
(x || y) = true x = true y = true
@[simp]
theorem Bool.or_eq_false_iff {x y : Bool} :
(x || y) = false x = false y = false

eq/beq/bne #

@[simp]

These two rules follow trivially by simp, but are needed to avoid non-termination in false_eq and true_eq.

@[simp]
theorem Bool.false_eq (b : Bool) :
(false = b) = (b = false)
@[simp]
theorem Bool.true_eq (b : Bool) :
(true = b) = (b = true)
@[simp]
theorem Bool.true_beq (b : Bool) :
(true == b) = b
@[simp]
theorem Bool.false_beq (b : Bool) :
(false == b) = !b
@[simp]
theorem Bool.true_bne (b : Bool) :
(true != b) = !b
@[simp]
theorem Bool.false_bne (b : Bool) :
(false != b) = b
@[simp]
theorem Bool.bne_true (b : Bool) :
(b != true) = !b
@[simp]
theorem Bool.bne_false (b : Bool) :
(b != false) = b
@[simp]
theorem Bool.not_beq_self (x : Bool) :
((!x) == x) = false
@[simp]
theorem Bool.beq_not_self (x : Bool) :
(x == !x) = false
@[simp]
theorem Bool.not_bne (a b : Bool) :
((!a) != b) = !a != b
@[simp]
theorem Bool.bne_not (a b : Bool) :
(a != !b) = !a != b
theorem Bool.not_bne_self (x : Bool) :
((!x) != x) = true
theorem Bool.bne_not_self (x : Bool) :
(x != !x) = true
@[simp]
theorem Bool.not_eq_self (b : Bool) :
(!b) = b False
@[simp]
theorem Bool.eq_not_self (b : Bool) :
@[simp]
theorem Bool.beq_self_left (a b : Bool) :
(a == (a == b)) = b
@[simp]
theorem Bool.beq_self_right (a b : Bool) :
((a == b) == b) = a
@[simp]
theorem Bool.bne_self_left (a b : Bool) :
(a != (a != b)) = b
@[simp]
theorem Bool.bne_self_right (a b : Bool) :
((a != b) != b) = a
theorem Bool.not_bne_not (x y : Bool) :
((!x) != !y) = (x != y)
@[simp]
theorem Bool.bne_assoc (x y z : Bool) :
((x != y) != z) = (x != (y != z))
instance Bool.instAssociativeBne :
Std.Associative fun (x1 x2 : Bool) => x1 != x2
Equations
@[simp]
theorem Bool.bne_left_inj {x y z : Bool} :
(x != y) = (x != z) y = z
@[simp]
theorem Bool.bne_right_inj {x y z : Bool} :
(x != z) = (y != z) x = y
theorem Bool.eq_not_of_ne {x y : Bool} :
x yx = !y
theorem Bool.beq_eq_decide_eq {α : Type u_1} [BEq α] [LawfulBEq α] [DecidableEq α] (a b : α) :
(a == b) = decide (a = b)
theorem Bool.eq_not {a b : Bool} :
a = !b a b
theorem Bool.not_eq {a b : Bool} :
(!a) = b a b
@[simp]
theorem Bool.coe_iff_coe {a b : Bool} :
(a = true b = true) a = b
@[simp]
theorem Bool.coe_true_iff_false {a b : Bool} :
(a = true b = false) a = !b
@[simp]
theorem Bool.coe_false_iff_true {a b : Bool} :
(a = false b = true) (!a) = b
@[simp]
theorem Bool.coe_false_iff_false {a b : Bool} :
(a = false b = false) (!a) = !b

beq properties #

theorem Bool.beq_comm {α : Type u_1} [BEq α] [LawfulBEq α] {a b : α} :
(a == b) = (b == a)

xor #

theorem Bool.false_xor (x : Bool) :
(false ^^ x) = x
theorem Bool.xor_false (x : Bool) :
(x ^^ false) = x
theorem Bool.true_xor (x : Bool) :
(true ^^ x) = !x
theorem Bool.xor_true (x : Bool) :
(x ^^ true) = !x
theorem Bool.not_xor_self (x : Bool) :
(!x ^^ x) = true
theorem Bool.xor_not_self (x : Bool) :
(x ^^ !x) = true
theorem Bool.not_xor (x y : Bool) :
(!x ^^ y) = !(x ^^ y)
theorem Bool.xor_not (x y : Bool) :
(x ^^ !y) = !(x ^^ y)
theorem Bool.not_xor_not (x y : Bool) :
(!x ^^ !y) = (x ^^ y)
theorem Bool.xor_self (x : Bool) :
(x ^^ x) = false
theorem Bool.xor_comm (x y : Bool) :
(x ^^ y) = (y ^^ x)
theorem Bool.xor_left_comm (x y z : Bool) :
(x ^^ (y ^^ z)) = (y ^^ (x ^^ z))
theorem Bool.xor_right_comm (x y z : Bool) :
(x ^^ y ^^ z) = (x ^^ z ^^ y)
theorem Bool.xor_assoc (x y z : Bool) :
(x ^^ y ^^ z) = (x ^^ (y ^^ z))
theorem Bool.xor_left_inj {x y z : Bool} :
(x ^^ y) = (x ^^ z) y = z
theorem Bool.xor_right_inj {x y z : Bool} :
(x ^^ z) = (y ^^ z) x = y

le/lt #

@[simp]
theorem Bool.le_true (x : Bool) :
@[simp]
theorem Bool.false_le (x : Bool) :
@[simp]
theorem Bool.le_refl (x : Bool) :
x x
@[simp]
theorem Bool.lt_irrefl (x : Bool) :
¬x < x
theorem Bool.le_trans {x y z : Bool} :
x yy zx z
theorem Bool.le_antisymm {x y : Bool} :
x yy xx = y
theorem Bool.le_total (x y : Bool) :
x y y x
theorem Bool.lt_asymm {x y : Bool} :
x < y¬y < x
theorem Bool.lt_trans {x y z : Bool} :
x < yy < zx < z
theorem Bool.lt_iff_le_not_le {x y : Bool} :
x < y x y ¬y x
theorem Bool.lt_of_le_of_lt {x y z : Bool} :
x yy < zx < z
theorem Bool.lt_of_lt_of_le {x y z : Bool} :
x < yy zx < z
theorem Bool.le_of_lt {x y : Bool} :
x < yx y
theorem Bool.le_of_eq {x y : Bool} :
x = yx y
theorem Bool.ne_of_lt {x y : Bool} :
x < yx y
theorem Bool.lt_of_le_of_ne {x y : Bool} :
x yx yx < y
theorem Bool.le_of_lt_or_eq {x y : Bool} :
x < y x = yx y

min/max #

@[simp]
theorem Bool.max_eq_or :
max = or
@[simp]
theorem Bool.min_eq_and :
min = and

injectivity lemmas #

theorem Bool.not_inj {x y : Bool} :
(!x) = !yx = y
theorem Bool.not_inj_iff {x y : Bool} :
(!x) = !y x = y
theorem Bool.and_or_inj_right {m x y : Bool} :
(x && m) = (y && m)(x || m) = (y || m)x = y
theorem Bool.and_or_inj_right_iff {m x y : Bool} :
(x && m) = (y && m) (x || m) = (y || m) x = y
theorem Bool.and_or_inj_left {m x y : Bool} :
(m && x) = (m && y)(m || x) = (m || y)x = y
theorem Bool.and_or_inj_left_iff {m x y : Bool} :
(m && x) = (m && y) (m || x) = (m || y) x = y

toNat #

def Bool.toNat (b : Bool) :

convert a Bool to a Nat, false -> 0, true -> 1

Equations
  • b.toNat = bif b then 1 else 0
@[simp]
theorem Bool.toNat_false :
false.toNat = 0
@[simp]
theorem Bool.toNat_true :
true.toNat = 1
theorem Bool.toNat_le (c : Bool) :
c.toNat 1
theorem Bool.toNat_lt (b : Bool) :
b.toNat < 2
@[simp]
theorem Bool.toNat_eq_zero {b : Bool} :
b.toNat = 0 b = false
@[simp]
theorem Bool.toNat_eq_one {b : Bool} :
b.toNat = 1 b = true

ite #

@[simp]
theorem Bool.if_true_left (p : Prop) [h : Decidable p] (f : Bool) :
(if p then true else f) = (decide p || f)
@[simp]
theorem Bool.if_false_left (p : Prop) [h : Decidable p] (f : Bool) :
(if p then false else f) = (!decide p && f)
@[simp]
theorem Bool.if_true_right (p : Prop) [h : Decidable p] (t : Bool) :
(if p then t else true) = (!decide p || t)
@[simp]
theorem Bool.if_false_right (p : Prop) [h : Decidable p] (t : Bool) :
(if p then t else false) = (decide p && t)
@[simp]
theorem Bool.ite_eq_true_distrib (p : Prop) [h : Decidable p] (t f : Bool) :
((if p then t else f) = true) = if p then t = true else f = true
@[simp]
theorem Bool.ite_eq_false_distrib (p : Prop) [h : Decidable p] (t f : Bool) :
((if p then t else f) = false) = if p then t = false else f = false
@[simp]
theorem Bool.ite_eq_false {b : Bool} {p q : Prop} :
(if b = false then p else q) if b = true then q else p
@[simp]
theorem Bool.ite_eq_true_else_eq_false {b : Bool} {q : Prop} :
(if b = true then q else b = false) b = trueq
@[simp]
theorem Bool.not_ite_eq_true_eq_true {p : Prop} [h : Decidable p] {b c : Bool} :
(¬if p then b = true else c = true) if p then b = false else c = false
@[simp]
theorem Bool.not_ite_eq_false_eq_false {p : Prop} [h : Decidable p] {b c : Bool} :
(¬if p then b = false else c = false) if p then b = true else c = true
@[simp]
theorem Bool.not_ite_eq_true_eq_false {p : Prop} [h : Decidable p] {b c : Bool} :
(¬if p then b = true else c = false) if p then b = false else c = true
@[simp]
theorem Bool.not_ite_eq_false_eq_true {p : Prop} [h : Decidable p] {b c : Bool} :
(¬if p then b = false else c = true) if p then b = true else c = false

forall #

theorem Bool.forall_bool' {p : BoolProp} (b : Bool) :
(∀ (x : Bool), p x) p b p !b
@[simp]
theorem Bool.forall_bool {p : BoolProp} :
(∀ (b : Bool), p b) p false p true

exists #

theorem Bool.exists_bool' {p : BoolProp} (b : Bool) :
(∃ (x : Bool), p x) p b p !b
@[simp]
theorem Bool.exists_bool {p : BoolProp} :
(∃ (b : Bool), p b) p false p true

cond #

theorem Bool.cond_eq_ite {α : Type u_1} (b : Bool) (t e : α) :
(bif b then t else e) = if b = true then t else e
theorem Bool.cond_eq_if {b : Bool} {α✝ : Type u_1} {x y : α✝} :
(bif b then x else y) = if b = true then x else y
@[simp]
theorem Bool.cond_not {α : Type u_1} (b : Bool) (t e : α) :
(bif !b then t else e) = bif b then e else t
@[simp]
theorem Bool.cond_self {α : Type u_1} (c : Bool) (t : α) :
(bif c then t else t) = t
@[simp]
theorem Bool.cond_prop {b : Bool} {p q : Prop} :
(bif b then p else q) if b = true then p else q

If the return values are propositions, there is no harm in simplifying a bif to an if.

theorem Bool.cond_decide {α : Type u_1} (p : Prop) [Decidable p] (t e : α) :
(bif decide p then t else e) = if p then t else e
@[simp]
theorem Bool.cond_eq_ite_iff {α : Type u_1} {a : Bool} {p : Prop} [h : Decidable p] {x y u v : α} :
((bif a then x else y) = if p then u else v) (if a = true then x else y) = if p then u else v
@[simp]
theorem Bool.ite_eq_cond_iff {α : Type u_1} {p : Prop} {a : Bool} [h : Decidable p] {x y u v : α} :
((if p then x else y) = bif a then u else v) (if p then x else y) = if a = true then u else v
@[simp]
theorem Bool.cond_eq_true_distrib (c t f : Bool) :
((bif c then t else f) = true) = if c = true then t = true else f = true
@[simp]
theorem Bool.cond_eq_false_distrib (c t f : Bool) :
((bif c then t else f) = false) = if c = true then t = false else f = false
theorem Bool.cond_true {α : Type u} {a b : α} :
(bif true then a else b) = a
theorem Bool.cond_false {α : Type u} {a b : α} :
(bif false then a else b) = b
@[simp]
theorem Bool.cond_true_left (c f : Bool) :
(bif c then true else f) = (c || f)
@[simp]
theorem Bool.cond_false_left (c f : Bool) :
(bif c then false else f) = (!c && f)
@[simp]
theorem Bool.cond_true_right (c t : Bool) :
(bif c then t else true) = (!c || t)
@[simp]
theorem Bool.cond_false_right (c t : Bool) :
(bif c then t else false) = (c && t)
@[simp]
theorem Bool.cond_true_not_same (c b : Bool) :
(bif c then !c else b) = (!c && b)
@[simp]
theorem Bool.cond_false_not_same (c b : Bool) :
(bif c then b else !c) = (!c || b)
@[simp]
theorem Bool.cond_true_same (c b : Bool) :
(bif c then c else b) = (c || b)
@[simp]
theorem Bool.cond_false_same (c b : Bool) :
(bif c then b else c) = (c && b)
theorem Bool.cond_pos {α : Type u_1} {b : Bool} {a a' : α} (h : b = true) :
(bif b then a else a') = a
theorem Bool.cond_neg {α : Type u_1} {b : Bool} {a a' : α} (h : b = false) :
(bif b then a else a') = a'
theorem Bool.apply_cond {α : Type u_1} {β : Type u_2} (f : αβ) {b : Bool} {a a' : α} :
f (bif b then a else a') = bif b then f a else f a'

decidability #

theorem Bool.decide_coe (b : Bool) [Decidable (b = true)] :
decide (b = true) = b
@[simp]
theorem Bool.decide_and (p q : Prop) [dpq : Decidable (p q)] [dp : Decidable p] [dq : Decidable q] :
decide (p q) = (decide p && decide q)
@[simp]
theorem Bool.decide_or (p q : Prop) [dpq : Decidable (p q)] [dp : Decidable p] [dq : Decidable q] :
decide (p q) = (decide p || decide q)
@[simp]
theorem Bool.decide_iff_dist (p q : Prop) [dpq : Decidable (p q)] [dp : Decidable p] [dq : Decidable q] :
decide (p q) = (decide p == decide q)
theorem Bool.and_eq_decide (p q : Prop) [dpq : Decidable (p q)] [dp : Decidable p] [dq : Decidable q] :
(decide p && decide q) = decide (p q)
theorem Bool.or_eq_decide (p q : Prop) [dpq : Decidable (p q)] [dp : Decidable p] [dq : Decidable q] :
(decide p || decide q) = decide (p q)
theorem Bool.decide_beq_decide (p q : Prop) [dpq : Decidable (p q)] [dp : Decidable p] [dq : Decidable q] :
(decide p == decide q) = decide (p q)

decide #

@[simp]
theorem false_eq_decide_iff {p : Prop} [h : Decidable p] :
@[simp]
theorem true_eq_decide_iff {p : Prop} [h : Decidable p] :

coercions #

def boolPredToPred {α : Sort u_1} :
Coe (αBool) (αProp)

This should not be turned on globally as an instance because it degrades performance in Mathlib, but may be used locally.

Equations
  • boolPredToPred = { coe := fun (r : αBool) (a : α) => r a = true }
def boolRelToRel {α : Sort u_1} :
Coe (ααBool) (ααProp)

This should not be turned on globally as an instance because it degrades performance in Mathlib, but may be used locally.

Equations
  • boolRelToRel = { coe := fun (r : ααBool) (a b : α) => r a b = true }