lean2/library/init/datatypes.lean

112 lines
2.7 KiB
Text

/-
Copyright (c) 2014 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Leonardo de Moura
Basic datatypes
-/
prelude
notation `Prop` := Type.{0}
notation [parsing-only] `Type'` := Type.{_+1}
notation [parsing-only] `Type₊` := Type.{_+1}
notation `Type₁` := Type.{1}
notation `Type₂` := Type.{2}
notation `Type₃` := Type.{3}
set_option structure.eta_thm true
set_option structure.proj_mk_thm true
inductive unit.{l} : Type.{l} :=
star : unit
inductive true : Prop :=
intro : true
inductive false : Prop
inductive empty : Type
inductive eq {A : Type} (a : A) : A → Prop :=
refl : eq a a
inductive heq {A : Type} (a : A) : Π {B : Type}, B → Prop :=
refl : heq a a
structure prod (A B : Type) :=
mk :: (pr1 : A) (pr2 : B)
inductive and (a b : Prop) : Prop :=
intro : a → b → and a b
definition and.elim_left {a b : Prop} (H : and a b) : a :=
and.rec (λa b, a) H
definition and.left := @and.elim_left
definition and.elim_right {a b : Prop} (H : and a b) : b :=
and.rec (λa b, b) H
definition and.right := @and.elim_right
inductive sum (A B : Type) : Type :=
inl {} : A → sum A B,
inr {} : B → sum A B
definition sum.intro_left [reducible] {A : Type} (B : Type) (a : A) : sum A B :=
sum.inl a
definition sum.intro_right [reducible] (A : Type) {B : Type} (b : B) : sum A B :=
sum.inr b
inductive or (a b : Prop) : Prop :=
inl {} : a → or a b,
inr {} : b → or a b
definition or.intro_left {a : Prop} (b : Prop) (Ha : a) : or a b :=
or.inl Ha
definition or.intro_right (a : Prop) {b : Prop} (Hb : b) : or a b :=
or.inr Hb
-- pos_num and num are two auxiliary datatypes used when parsing numerals such as 13, 0, 26.
-- The parser will generate the terms (pos (bit1 (bit1 (bit0 one)))), zero, and (pos (bit0 (bit1 (bit1 one)))).
-- This representation can be coerced in whatever we want (e.g., naturals, integers, reals, etc).
inductive pos_num : Type :=
one : pos_num,
bit1 : pos_num → pos_num,
bit0 : pos_num → pos_num
namespace pos_num
definition succ (a : pos_num) : pos_num :=
rec_on a (bit0 one) (λn r, bit0 r) (λn r, bit1 n)
end pos_num
inductive num : Type :=
zero : num,
pos : pos_num → num
namespace num
open pos_num
definition succ (a : num) : num :=
rec_on a (pos one) (λp, pos (succ p))
end num
inductive bool : Type :=
ff : bool,
tt : bool
inductive char : Type :=
mk : bool → bool → bool → bool → bool → bool → bool → bool → char
inductive string : Type :=
empty : string,
str : char → string → string
inductive nat :=
zero : nat,
succ : nat → nat
inductive option (A : Type) : Type :=
none {} : option A,
some : A → option A