lean4-htt/library/system/io.lean
2017-03-22 23:36:05 -07:00

147 lines
4.4 KiB
Text
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/-
Copyright (c) 2016 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Authors: Luke Nelson, Jared Roesch and Leonardo de Moura
-/
import data.buffer
inductive io.error_kind
| not_found | permission_denied | connection_refused
| connection_reset | connection_aborted | not_connected
| addr_in_use | addr_not_available | broken_pipe
| already_exists | would_block | invalid_input
| invalid_data | timeout | write_zero | interrupted
| unexpected_eof
inductive io.error
| other : string → io.error
| sys : nat → io.error
| primitive : io.error_kind → io.error
structure io.terminal (m : Type → Type → Type) :=
(put_str : string → m io.error unit)
(get_line : m io.error string)
inductive io.mode
| read | write | read_write | append
structure io.handle :=
(id : nat)
structure io.file_system (m : Type → Type → Type) :=
/- Remark: in Haskell, they also provide (Maybe TextEncoding) and NewlineMode -/
(mk_file_handle : string → io.mode → bool → m io.error io.handle)
(file_size : io.handle → m io.error nat)
(is_eof : io.handle → m io.error bool)
(look_ahead : io.handle → m io.error char)
(flush : io.handle → m io.error unit)
(close : io.handle → m io.error unit)
(read : io.handle → nat → m io.error char_buffer)
(write : io.handle → char_buffer → m io.error unit)
(get_line : io.handle → m io.error char_buffer)
structure io.interface :=
(m : Type → Type → Type)
(return : Π e α, α → m e α)
(bind : Π e α β, m e α → (α → m e β) → m e β)
(catch : Π e₁ e₂ α, m e₁ α → (e₁ → m e₂ α) → m e₂ α)
(fail : Π e α, e → m e α)
(term : io.terminal m)
(fs : io.file_system m)
def io_core (e : Type) (α : Type) :=
Π (ioi : io.interface), ioi^.m e α
@[reducible] def io (α : Type) :=
io_core io.error α
protected def io_core.pure (e : Type) (α : Type) (a : α) : io_core e α :=
λ i, i^.return e α a
protected def io_core.bind (e : Type) (α β : Type) (a : io_core e α) (b : α → io_core e β) : io_core e β :=
λ i, i^.bind e α β (a i) (λ v, b v i)
instance io_core_is_monad (e : Type) : monad (io_core e) :=
{ pure := io_core.pure e,
bind := io_core.bind e }
protected def io.fail (α : Type) (s : string) : io α :=
λ i, i^.fail io.error α (io.error.other s)
instance : monad_fail io :=
{ pure := io_core.pure io.error,
bind := io_core.bind io.error,
fail := io.fail }
namespace io
def put_str (s : string) : io unit :=
λ i, i^.term^.put_str s
def put_str_ln (s : string) : io unit :=
put_str s >> put_str "\n"
def get_line : io string :=
λ i, i^.term^.get_line
def print {α} [has_to_string α] (s : α) : io unit :=
put_str ∘ to_string $ s
def print_ln {α} [has_to_string α] (s : α) : io unit :=
print s >> put_str "\n"
def mk_file_handle (s : string) (m : mode) (bin : bool := ff) : io handle :=
λ i, i^.fs^.mk_file_handle s m bin
def pfail {α} (k : io.error_kind) : io α :=
λ i, i^.fail io.error α (io.error.primitive k)
namespace fs
def size (h : handle) : io nat :=
λ i, i^.fs^.file_size h
def is_eof (h : handle) : io bool :=
λ i, i^.fs^.is_eof h
def look_ahead (h : handle) : io char :=
λ i, i^.fs^.look_ahead h
def flush (h : handle) : io unit :=
λ i, i^.fs^.flush h
def close (h : handle) : io unit :=
λ i, i^.fs^.close h
def read (h : handle) (n : nat) : io char_buffer :=
λ i, i^.fs^.read h n
def write (h : handle) (b : char_buffer) : io unit :=
λ i, i^.fs^.write h b
def get_char (h : handle) : io char :=
do b ← read h 1,
if h : b^.size = 1 then return $ b^.read ⟨0, h^.symm ▸ zero_lt_one⟩
else pfail error_kind.unexpected_eof
def get_line (h : handle) : io char_buffer :=
λ i, i^.fs^.get_line h
def put_char (h : handle) (c : char) : io unit :=
do write h (mk_buffer^.push_back c)
end fs
def read_file (s : string) (bin := ff) : io char_buffer :=
do h ← mk_file_handle s mode.read bin,
sz ← fs.size h,
fs.read h sz
end io
meta constant format.print_using : format → options → io unit
meta definition format.print (fmt : format) : io unit :=
format.print_using fmt options.mk
meta definition pp_using {α : Type} [has_to_format α] (a : α) (o : options) : io unit :=
format.print_using (to_fmt a) o
meta definition pp {α : Type} [has_to_format α] (a : α) : io unit :=
format.print (to_fmt a)