254 lines
9.4 KiB
Text
254 lines
9.4 KiB
Text
namespace Lean
|
||
namespace Parser
|
||
|
||
abbrev Pos := String.Pos
|
||
|
||
/-
|
||
σ is the non-backtrackable State
|
||
δ is the backtrackable State
|
||
μ is the extra error Message data
|
||
-/
|
||
inductive Result (σ δ μ α : Type)
|
||
| ok {} (a : α) (i : Pos) (st : σ) (bst : δ) (eps : Bool) : Result
|
||
| error {} (msg : String) (i : Pos) (st : σ) (extra : Option μ) (eps : Bool) : Result
|
||
|
||
inductive Result.IsOk {σ δ μ α : Type} : Result σ δ μ α → Prop
|
||
| mk (a : α) (i : Pos) (st : σ) (bst : δ) (eps : Bool) : Result.IsOk (Result.ok a i st bst eps)
|
||
|
||
theorem errorIsNotOk {σ δ μ α : Type} {msg : String} {i : Pos} {st : σ} {extra : Option μ} {eps : Bool}
|
||
(h : Result.IsOk (@Result.error σ δ μ α msg i st extra eps)) : False :=
|
||
match h with end
|
||
|
||
@[inline] def unreachableError {σ δ μ α β : Type} {msg : String} {i : Pos} {st : σ} {extra : Option μ} {eps : Bool}
|
||
(h : Result.IsOk (@Result.error σ δ μ α msg i st extra eps)) : β :=
|
||
False.elim (errorIsNotOk h)
|
||
|
||
def input (σ δ μ : Type) : Type := { r : Result σ δ μ Unit // r.IsOk }
|
||
|
||
@[inline] def mkInput {σ δ μ : Type} (i : Pos) (st : σ) (bst : δ) (eps := true) : input σ δ μ :=
|
||
⟨Result.ok () i st bst eps, Result.IsOk.mk _ _ _ _ _⟩
|
||
|
||
def ParserM (σ δ μ α : Type) :=
|
||
String → input σ δ μ → Result σ δ μ α
|
||
|
||
variables {σ δ μ α β : Type}
|
||
|
||
namespace ParserM
|
||
|
||
protected def default : ParserM σ δ μ α :=
|
||
λ _ inp,
|
||
match inp with
|
||
| ⟨Result.ok _ i st bst _, h⟩ := Result.error "" i st none true
|
||
| ⟨Result.error _ _ _ _ _, h⟩ := unreachableError h
|
||
|
||
instance : Inhabited (ParserM σ δ μ α) :=
|
||
⟨ParserM.default⟩
|
||
|
||
@[inline] def run (p : ParserM σ δ μ α) (st : σ) (bst : δ) (s : String) : Result σ δ μ α :=
|
||
p s (mkInput 0 st bst)
|
||
|
||
@[inline] def pure (a : α) : ParserM σ δ μ α :=
|
||
λ _ inp,
|
||
match inp with
|
||
| ⟨Result.ok _ it st bst _, h⟩ := Result.ok a it st bst true
|
||
| ⟨Result.error _ _ _ _ _, h⟩ := unreachableError h
|
||
|
||
@[inline] def bind (x : ParserM σ δ μ α) (f : α → ParserM σ δ μ β) : ParserM σ δ μ β :=
|
||
λ str inp,
|
||
match x str inp with
|
||
| Result.ok a i st bst e₁ :=
|
||
(match f a str (mkInput i st bst) with
|
||
| Result.ok b i st bst e₂ := Result.ok b i st bst (strictAnd e₁ e₂)
|
||
| Result.error msg i st ext e₂ := Result.error msg i st ext (strictAnd e₁ e₂))
|
||
| Result.error msg i st etx e := Result.error msg i st etx e
|
||
|
||
instance isMonad : Monad (ParserM σ δ μ) :=
|
||
{pure := @ParserM.pure _ _ _, bind := @ParserM.bind _ _ _}
|
||
|
||
def mkError (r : input σ δ μ) (msg : String) (eps := true) : Result σ δ μ α :=
|
||
match r with
|
||
| ⟨Result.ok _ i c s _, _⟩ := Result.error msg i c none eps
|
||
| ⟨Result.error _ _ _ _ _, h⟩ := unreachableError h
|
||
|
||
@[inline] def orelse (p q : ParserM σ δ μ α) : ParserM σ δ μ α :=
|
||
λ str inp,
|
||
match inp with
|
||
| ⟨Result.ok _ i₁ _ bst₁ _, _⟩ :=
|
||
(match p str inp with
|
||
| Result.error _ _ st₂ _ tt := q str (mkInput i₁ st₂ bst₁)
|
||
| other := other)
|
||
| ⟨Result.error _ _ _ _ _, h⟩ := unreachableError h
|
||
|
||
@[inline] def failure : ParserM σ δ μ α :=
|
||
λ _ inp, mkError inp "failure"
|
||
|
||
instance : Alternative (ParserM σ δ μ) :=
|
||
{ orelse := @ParserM.orelse _ _ _,
|
||
failure := @ParserM.failure _ _ _,
|
||
.. ParserM.isMonad }
|
||
|
||
def setSilentError : Result σ δ μ α → Result σ δ μ α
|
||
| (Result.error msg i st ext _) := Result.error msg i st ext true
|
||
| other := other
|
||
|
||
@[inline] def currPos : input σ δ μ → Pos
|
||
| ⟨Result.ok _ i _ _ _, _⟩ := i
|
||
| ⟨Result.error _ _ _ _ _, h⟩ := unreachableError h
|
||
|
||
@[inline] def try {α : Type} (p : ParserM σ δ μ α) : ParserM σ δ μ α :=
|
||
λ str inp, setSilentError (p str inp)
|
||
|
||
@[inline] def lookahead (p : ParserM σ δ μ α) : ParserM σ δ μ α :=
|
||
λ str inp,
|
||
match inp with
|
||
| ⟨Result.ok _ i _ bst _, _⟩ :=
|
||
(match p str inp with
|
||
| Result.ok a _ st _ _ := Result.ok a i st bst true
|
||
| other := other)
|
||
| ⟨Result.error _ _ _ _ _, h⟩ := unreachableError h
|
||
|
||
@[specialize] def satisfy (p : Char → Bool) : ParserM σ δ μ Char :=
|
||
λ str inp,
|
||
match inp with
|
||
| ⟨Result.ok _ i st bst _, _⟩ :=
|
||
if str.atEnd i then mkError inp "end of input"
|
||
else let c := str.get i in
|
||
if p c then Result.ok c (str.next i) st bst false
|
||
else mkError inp "unexpected character"
|
||
| ⟨Result.error _ _ _ _ _, h⟩ := unreachableError h
|
||
|
||
@[specialize] partial def takeUntilAux (p : Char → Bool) : ParserM σ δ μ Unit
|
||
| str inp :=
|
||
match inp with
|
||
| ⟨Result.ok _ i st bst _, _⟩ :=
|
||
if str.atEnd i then inp.val
|
||
else let c := str.get i in
|
||
if p c then inp.val
|
||
else takeUntilAux str (mkInput (str.next i) st bst false)
|
||
| ⟨Result.error _ _ _ _ _, h⟩ := unreachableError h
|
||
|
||
@[inline] def takeUntil (p : Char → Bool) : ParserM σ δ μ Unit :=
|
||
λ str inp, takeUntilAux p str inp
|
||
|
||
partial def strAux (s : String) (errorMsg : String) : Pos → ParserM σ δ μ Unit
|
||
| j str inp :=
|
||
if s.atEnd j then inp.val
|
||
else match inp with
|
||
| ⟨Result.ok _ i st bst _, _⟩ :=
|
||
if str.atEnd i then mkError inp errorMsg
|
||
else if s.get j == str.get i then strAux (s.next j) str (mkInput (str.next i) st bst false)
|
||
else mkError inp errorMsg
|
||
| ⟨Result.error _ _ _ _ _, h⟩ := unreachableError h
|
||
|
||
@[inline] def str (s : String) : ParserM σ δ μ Unit :=
|
||
strAux s ("expected '" ++ repr s ++ "'") 0
|
||
|
||
@[specialize] partial def manyLoop (a : α) (p : ParserM σ δ μ α) : Bool → ParserM σ δ μ α
|
||
| fst str inp :=
|
||
match inp with
|
||
| ⟨Result.ok _ i₀ _ bst₀ _, _⟩ :=
|
||
(match p str inp with
|
||
| Result.ok _ i st bst _ := manyLoop false str (mkInput i st bst)
|
||
| Result.error _ _ st _ _ := Result.ok a i₀ st bst₀ fst)
|
||
| ⟨Result.error _ _ _ _ _, h⟩ := unreachableError h
|
||
|
||
-- Auxiliary Function used to lift manyAux
|
||
@[inline] def manyAux (a : α) (p : ParserM σ δ μ α) : ParserM σ δ μ α :=
|
||
manyLoop a p true
|
||
|
||
@[inline] def many (p : ParserM σ δ μ Unit) : ParserM σ δ μ Unit :=
|
||
manyAux () p
|
||
|
||
@[inline] def many1 (p : ParserM σ δ μ Unit) : ParserM σ δ μ Unit :=
|
||
p *> many p
|
||
|
||
end ParserM
|
||
|
||
class monadParser (σ : outParam Type) (δ : outParam Type) (μ : outParam Type) (m : Type → Type) :=
|
||
(lift {} {α : Type} : ParserM σ δ μ α → m α)
|
||
(map {} {α : Type} : (Π β, ParserM σ δ μ β → ParserM σ δ μ β) → m α → m α)
|
||
|
||
instance monadParserBase : monadParser σ δ μ (ParserM σ δ μ) :=
|
||
{ lift := λ α, id,
|
||
map := λ α f x, f α x }
|
||
|
||
instance monadParserTrans {m n : Type → Type} [HasMonadLift m n] [MonadFunctor m m n n] [monadParser σ δ μ m] : monadParser σ δ μ n :=
|
||
{ lift := λ α p, monadLift (monadParser.lift p : m α),
|
||
map := λ α f x, monadMap (λ β x, (monadParser.map @f x : m β)) x }
|
||
|
||
class monadParserAux (σ : outParam Type) (δ : outParam Type) (μ : outParam Type) (m : Type → Type) :=
|
||
(map {} {α : Type} : (ParserM σ δ μ α → ParserM σ δ μ α) → m α → m α)
|
||
|
||
instance monadParserAuxBase : monadParserAux σ δ μ (ParserM σ δ μ) :=
|
||
{ map := λ α, id }
|
||
|
||
instance monadParserAuxReader {m : Type → Type} {ρ : Type} [Monad m] [monadParserAux σ δ μ m] : monadParserAux σ δ μ (ReaderT ρ m) :=
|
||
{ map := λ α f x r, (monadParserAux.map f : m α → m α) (x r) }
|
||
|
||
section
|
||
variables {m : Type → Type} [monadParser σ δ μ m]
|
||
|
||
@[inline] def satisfy (p : Char → Bool) : m Char := monadParser.lift (ParserM.satisfy p)
|
||
def ch (c : Char) : m Char := satisfy (= c)
|
||
def alpha : m Char := satisfy Char.isAlpha
|
||
def digit : m Char := satisfy Char.isDigit
|
||
def upper : m Char := satisfy Char.isUpper
|
||
def lower : m Char := satisfy Char.isLower
|
||
def any : m Char := satisfy (λ _, True)
|
||
|
||
@[inline] def takeUntil (p : Char → Bool) : m Unit := monadParser.lift (ParserM.takeUntil p)
|
||
|
||
@[inline] def str (s : String) : m Unit := monadParser.lift (ParserM.str s)
|
||
|
||
@[inline] def lookahead (p : m α) : m α :=
|
||
monadParser.map (λ β p, ParserM.lookahead p) p
|
||
|
||
@[inline] def takeWhile (p : Char → Bool) : m Unit := takeUntil (λ c, !p c)
|
||
|
||
@[inline] def whitespace : m Unit := takeWhile Char.isWhitespace
|
||
|
||
end
|
||
|
||
section
|
||
variables {m : Type → Type} [monadParserAux σ δ μ m]
|
||
|
||
@[inline] def many (p : m Unit) : m Unit := monadParserAux.map ParserM.many p
|
||
@[inline] def many1 (p : m Unit) : m Unit := monadParserAux.map ParserM.many1 p
|
||
|
||
end
|
||
|
||
end Parser
|
||
end Lean
|
||
|
||
abbrev Parser := ReaderT Nat (Lean.Parser.ParserM Unit Unit Unit) Unit
|
||
|
||
open Lean.Parser
|
||
|
||
-- setOption pp.implicit True
|
||
-- setOption Trace.Compiler.boxed True
|
||
|
||
def testP : Parser :=
|
||
many1 (str "++" <|> str "**" <|> (str "--" *> takeUntil (= '\n') *> any *> pure ()))
|
||
|
||
def testParser (x : Parser) (input : String) : String :=
|
||
match (x 0).run () () input with
|
||
| Lean.Parser.Result.ok _ i _ _ _ := "Ok at " ++ toString i
|
||
| Result.error msg i _ _ _ := "Error at " ++ toString i ++ ": " ++ msg
|
||
|
||
@[noinline] def test (s : String) : IO Unit :=
|
||
IO.println (testParser testP s)
|
||
|
||
def mkBigString : Nat → String → String
|
||
| 0 s := s
|
||
| (n+1) s := mkBigString n (s ++ "-- new comment\n")
|
||
|
||
def prof {α : Type} (msg : String) (p : IO α) : IO α :=
|
||
let msg₁ := "Time for '" ++ msg ++ "':" in
|
||
let msg₂ := "Memory usage for '" ++ msg ++ "':" in
|
||
allocprof msg₂ (timeit msg₁ p)
|
||
|
||
def main (xs : List String) : IO Unit :=
|
||
let s₁ := mkBigString xs.head.toNat "" in
|
||
let s₂ := s₁ ++ "bad" ++ mkBigString 20 "" in
|
||
prof "Parser 1" (test s₁) *>
|
||
prof "Parser 2" (test s₂)
|