124 lines
4 KiB
Text
124 lines
4 KiB
Text
/-
|
||
Copyright (c) 2020 Microsoft Corporation. All rights reserved.
|
||
Released under Apache 2.0 license as described in the file LICENSE.
|
||
Authors: Leonardo de Moura
|
||
-/
|
||
import Lean.Message
|
||
import Lean.InternalExceptionId
|
||
import Lean.Data.Options
|
||
|
||
namespace Lean
|
||
|
||
/- Exception type used in most Lean monads -/
|
||
inductive Exception
|
||
| error (ref : Syntax) (msg : MessageData)
|
||
| internal (id : InternalExceptionId)
|
||
|
||
def Exception.toMessageData : Exception → MessageData
|
||
| Exception.error _ msg => msg
|
||
| Exception.internal id => id.toString
|
||
|
||
def Exception.getRef : Exception → Syntax
|
||
| Exception.error ref _ => ref
|
||
| Exception.internal _ => Syntax.missing
|
||
|
||
instance : Inhabited Exception := ⟨Exception.error (arbitrary _) (arbitrary _)⟩
|
||
|
||
class Ref (m : Type → Type) :=
|
||
(getRef : m Syntax)
|
||
(withRef {α} : Syntax → m α → m α)
|
||
|
||
export Ref (getRef)
|
||
|
||
instance (m n : Type → Type) [Ref m] [MonadFunctor m n] [MonadLift m n] : Ref n := {
|
||
getRef := liftM (getRef : m _),
|
||
withRef := fun ref x => monadMap (m := m) (Ref.withRef ref) x
|
||
}
|
||
|
||
def replaceRef (ref : Syntax) (oldRef : Syntax) : Syntax :=
|
||
match ref.getPos with
|
||
| some _ => ref
|
||
| _ => oldRef
|
||
|
||
@[inline] def withRef {m : Type → Type} [Monad m] [Ref m] {α} (ref : Syntax) (x : m α) : m α := do
|
||
let oldRef ← getRef
|
||
let ref := replaceRef ref oldRef
|
||
Ref.withRef ref x
|
||
|
||
/- Similar to `AddMessageContext`, but for error messages.
|
||
The default instance just uses `AddMessageContext`.
|
||
In error messages, we may want to provide additional information (e.g., macro expansion stack),
|
||
and refine the `(ref : Syntax)`. -/
|
||
class AddErrorMessageContext (m : Type → Type) :=
|
||
(add : Syntax → MessageData → m (Syntax × MessageData))
|
||
|
||
instance (m : Type → Type) [AddMessageContext m] [Monad m] : AddErrorMessageContext m := {
|
||
add := fun ref msg => do
|
||
msg ← addMessageContext msg
|
||
pure (ref, msg)
|
||
}
|
||
|
||
section Methods
|
||
|
||
variables {m : Type → Type} [Monad m] [MonadExceptOf Exception m] [Ref m] [AddErrorMessageContext m]
|
||
|
||
def throwError {α} (msg : MessageData) : m α := do
|
||
let ref ← getRef
|
||
let (ref, msg) ← AddErrorMessageContext.add ref msg
|
||
throw $ Exception.error ref msg
|
||
|
||
def throwUnknownConstant {α} (constName : Name) : m α :=
|
||
throwError msg!"unknown constant '{mkConst constName}'"
|
||
|
||
def throwErrorAt {α} (ref : Syntax) (msg : MessageData) : m α := do
|
||
withRef ref $ throwError msg
|
||
|
||
def ofExcept {ε α} [HasToString ε] (x : Except ε α) : m α :=
|
||
match x with
|
||
| Except.ok a => pure a
|
||
| Except.error e => throwError $ toString e
|
||
|
||
def throwKernelException {α} [MonadOptions m] (ex : KernelException) : m α := do
|
||
throwError $ ex.toMessageData (← getOptions)
|
||
|
||
end Methods
|
||
|
||
class MonadRecDepth (m : Type → Type) :=
|
||
(withRecDepth {α} : Nat → m α → m α)
|
||
(getRecDepth : m Nat)
|
||
(getMaxRecDepth : m Nat)
|
||
|
||
instance {ρ m} [Monad m] [MonadRecDepth m] : MonadRecDepth (ReaderT ρ m) := {
|
||
withRecDepth := fun d x ctx => MonadRecDepth.withRecDepth d (x ctx),
|
||
getRecDepth := fun _ => MonadRecDepth.getRecDepth,
|
||
getMaxRecDepth := fun _ => MonadRecDepth.getMaxRecDepth
|
||
}
|
||
|
||
instance {ω σ m} [Monad m] [MonadRecDepth m] : MonadRecDepth (StateRefT' ω σ m) :=
|
||
inferInstanceAs (MonadRecDepth (ReaderT _ _))
|
||
|
||
@[inline] def withIncRecDepth {α m} [Monad m] [MonadRecDepth m] [MonadExceptOf Exception m] [Ref m] [AddErrorMessageContext m]
|
||
(x : m α) : m α := do
|
||
let curr ← MonadRecDepth.getRecDepth
|
||
let max ← MonadRecDepth.getMaxRecDepth
|
||
if curr == max then throwError maxRecDepthErrorMessage
|
||
MonadRecDepth.withRecDepth (curr+1) x
|
||
|
||
syntax "throwError! " ((interpolatedStr term) <|> term) : term
|
||
syntax "throwErrorAt! " term:max ((interpolatedStr term) <|> term) : term
|
||
|
||
macro_rules
|
||
| `(throwError! $msg) =>
|
||
if msg.getKind == interpolatedStrKind then
|
||
`(throwError (msg! $msg))
|
||
else
|
||
`(throwError $msg)
|
||
|
||
macro_rules
|
||
| `(throwErrorAt! $ref $msg) =>
|
||
if msg.getKind == interpolatedStrKind then
|
||
`(throwErrorAt $ref (msg! $msg))
|
||
else
|
||
`(throwErrorAt $ref $msg)
|
||
|
||
end Lean
|