79 lines
2.7 KiB
Text
79 lines
2.7 KiB
Text
/-
|
||
Copyright (c) 2016 Microsoft Corporation. All rights reserved.
|
||
Released under Apache 2.0 license as described in the file LICENSE.
|
||
Author: Leonardo de Moura
|
||
-/
|
||
prelude
|
||
import init.data.string.basic init.data.subtype.basic
|
||
import init.data.uint init.data.prod init.data.sum.basic init.data.nat.div
|
||
import init.data.repr
|
||
open sum subtype nat
|
||
|
||
universes u v
|
||
|
||
class has_to_string (α : Type u) :=
|
||
(to_string : α → string)
|
||
|
||
def to_string {α : Type u} [has_to_string α] : α → string :=
|
||
has_to_string.to_string
|
||
|
||
instance : has_to_string string :=
|
||
⟨λ s, s⟩
|
||
|
||
instance : has_to_string string.iterator :=
|
||
⟨λ it, it.next_to_string⟩
|
||
|
||
instance : has_to_string bool :=
|
||
⟨λ b, cond b "tt" "ff"⟩
|
||
|
||
instance {p : Prop} : has_to_string (decidable p) :=
|
||
-- Remark: type class inference will not consider local instance `b` in the new elaborator
|
||
⟨λ b : decidable p, @ite p b _ "tt" "ff"⟩
|
||
|
||
protected def list.to_string_aux {α : Type u} [has_to_string α] : bool → list α → string
|
||
| b [] := ""
|
||
| tt (x::xs) := to_string x ++ list.to_string_aux ff xs
|
||
| ff (x::xs) := ", " ++ to_string x ++ list.to_string_aux ff xs
|
||
|
||
protected def list.to_string {α : Type u} [has_to_string α] : list α → string
|
||
| [] := "[]"
|
||
| (x::xs) := "[" ++ list.to_string_aux tt (x::xs) ++ "]"
|
||
|
||
instance {α : Type u} [has_to_string α] : has_to_string (list α) :=
|
||
⟨list.to_string⟩
|
||
|
||
instance : has_to_string unit :=
|
||
⟨λ u, "()"⟩
|
||
|
||
instance : has_to_string nat :=
|
||
⟨λ n, repr n⟩
|
||
|
||
instance : has_to_string char :=
|
||
⟨λ c, c.to_string⟩
|
||
|
||
instance (n : nat) : has_to_string (fin n) :=
|
||
⟨λ f, to_string (fin.val f)⟩
|
||
|
||
instance : has_to_string uint16 :=
|
||
⟨λ n, to_string (fin.val n)⟩
|
||
|
||
instance : has_to_string uint32 :=
|
||
⟨λ n, to_string (fin.val n)⟩
|
||
|
||
instance : has_to_string uint64 :=
|
||
⟨λ n, to_string (fin.val n)⟩
|
||
|
||
instance {α : Type u} [has_to_string α] : has_to_string (option α) :=
|
||
⟨λ o, match o with | none := "none" | (some a) := "(some " ++ to_string a ++ ")" end⟩
|
||
|
||
instance {α : Type u} {β : Type v} [has_to_string α] [has_to_string β] : has_to_string (α ⊕ β) :=
|
||
⟨λ s, match s with | (inl a) := "(inl " ++ to_string a ++ ")" | (inr b) := "(inr " ++ to_string b ++ ")" end⟩
|
||
|
||
instance {α : Type u} {β : Type v} [has_to_string α] [has_to_string β] : has_to_string (α × β) :=
|
||
⟨λ ⟨a, b⟩, "(" ++ to_string a ++ ", " ++ to_string b ++ ")"⟩
|
||
|
||
instance {α : Type u} {β : α → Type v} [has_to_string α] [s : ∀ x, has_to_string (β x)] : has_to_string (sigma β) :=
|
||
⟨λ ⟨a, b⟩, "⟨" ++ to_string a ++ ", " ++ to_string b ++ "⟩"⟩
|
||
|
||
instance {α : Type u} {p : α → Prop} [has_to_string α] : has_to_string (subtype p) :=
|
||
⟨λ s, to_string (val s)⟩
|