lean4-htt/library/init/meta/format.lean
2016-10-05 10:39:40 -07:00

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/-
Copyright (c) 2016 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Leonardo de Moura
-/
prelude
import init.meta.options
universe variables u v
inductive format.color
| red | green | orange | blue | pink | cyan | grey
meta constant format : Type 1
meta constant format.line : format
meta constant format.space : format
meta constant format.nil : format
meta constant format.compose : format → format → format
meta constant format.nest : nat → format → format
meta constant format.highlight : format → color → format
meta constant format.group : format → format
meta constant format.of_string : string → format
meta constant format.of_nat : nat → format
meta constant format.flatten : format → format
meta constant format.to_string : format → options → string
meta constant format.of_options : options → format
meta constant format.is_nil : format → bool
meta constant trace_fmt {A : Type u} : format → (unit → A) → A
meta instance : inhabited format :=
⟨format.space⟩
meta instance : has_append format :=
⟨format.compose⟩
meta instance : has_to_string format :=
⟨λ f, format.to_string f options.mk⟩
meta class has_to_format (A : Type u) :=
(to_format : A → format)
meta instance : has_to_format format :=
⟨id⟩
meta def to_fmt {A : Type u} [has_to_format A] : A → format :=
has_to_format.to_format
meta instance nat_to_format : has_coe nat format :=
⟨format.of_nat⟩
meta instance string_to_format : has_coe string format :=
⟨format.of_string⟩
open format list
meta def format.indent (f : format) (n : nat) : format :=
nest n (line ++ f)
meta def format.when {A : Type u} [has_to_format A] : bool → A → format
| tt a := to_fmt a
| ff a := nil
meta instance : has_to_format options :=
⟨λ o, format.of_options o⟩
meta instance : has_to_format bool :=
⟨λ b, if b then of_string "tt" else of_string "ff"⟩
meta instance {p : Prop} : has_to_format (decidable p) :=
⟨λ b : decidable p, @ite p b _ (of_string "tt") (of_string "ff")⟩
meta instance : has_to_format string :=
⟨λ s, format.of_string s⟩
meta instance : has_to_format nat :=
⟨λ n, format.of_nat n⟩
meta instance : has_to_format char :=
⟨λ c : char, format.of_string [c]⟩
meta def list.to_format_aux {A : Type u} [has_to_format A] : bool → list A → format
| b [] := to_fmt ""
| tt (x::xs) := to_fmt x ++ list.to_format_aux ff xs
| ff (x::xs) := to_fmt "," ++ line ++ to_fmt x ++ list.to_format_aux ff xs
meta def list.to_format {A : Type u} [has_to_format A] : list A → format
| [] := to_fmt "[]"
| (x::xs) := to_fmt "[" ++ group (nest 1 (list.to_format_aux tt (x::xs))) ++ to_fmt "]"
meta instance {A : Type u} [has_to_format A] : has_to_format (list A) :=
⟨list.to_format⟩
attribute [instance] string.has_to_format
meta instance : has_to_format name :=
⟨λ n, to_fmt (to_string n)⟩
meta instance : has_to_format unit :=
⟨λ u, to_fmt "()"⟩
meta instance {A : Type u} [has_to_format A] : has_to_format (option A) :=
⟨λ o, option.cases_on o
(to_fmt "none")
(λ a, to_fmt "(some " ++ nest 6 (to_fmt a) ++ to_fmt ")")⟩
meta instance {A : Type u} {B : Type v} [has_to_format A] [has_to_format B] : has_to_format (sum A B) :=
⟨λ s, sum.cases_on s
(λ a, to_fmt "(inl " ++ nest 5 (to_fmt a) ++ to_fmt ")")
(λ b, to_fmt "(inr " ++ nest 5 (to_fmt b) ++ to_fmt ")")⟩
open prod
meta instance {A : Type u} {B : Type v} [has_to_format A] [has_to_format B] : has_to_format (prod A B) :=
⟨λ p, group (nest 1 (to_fmt "(" ++ to_fmt (fst p) ++ to_fmt "," ++ line ++ to_fmt (snd p) ++ to_fmt ")"))⟩
open sigma
meta instance {A : Type u} {B : A → Type v} [has_to_format A] [s : ∀ x, has_to_format (B x)]
: has_to_format (sigma B) :=
⟨λ p, group (nest 1 (to_fmt "⟨" ++ to_fmt (fst p) ++ to_fmt "," ++ line ++ to_fmt (snd p) ++ to_fmt "⟩"))⟩
open subtype
meta instance {A : Type u} {P : A → Prop} [has_to_format A] : has_to_format (subtype P) :=
⟨λ s, to_fmt (elt_of s)⟩
meta def format.bracket : string → string → format → format
| o c f := to_fmt o ++ nest (utf8_length o) f ++ to_fmt c
meta def format.paren (f : format) : format :=
format.bracket "(" ")" f
meta def format.cbrace (f : format) : format :=
format.bracket "{" "}" f
meta def format.sbracket (f : format) : format :=
format.bracket "[" "]" f
meta def format.dcbrace (f : format) : format :=
to_fmt "⦃" ++ nest 1 f ++ to_fmt "⦄"