3a408e0e54
This PR changes the signature of `Array.get` to take a Nat and a proof, rather than a `Fin`, for consistency with the rest of the (planned) Array API. Note that because of bootstrapping issues we can't provide `get_elem_tactic` as an autoparameter for the proof. As users will mostly use the `xs[i]` notation provided by `GetElem`, this hopefully isn't a problem. We may restore `Fin` based versions, either here or downstream, as needed, but they won't be the "main" functions. --------- Co-authored-by: David Thrane Christiansen <david@davidchristiansen.dk>
44 lines
1.5 KiB
Text
44 lines
1.5 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
|
|
-/
|
|
prelude
|
|
import Init.System.IO
|
|
namespace Lean
|
|
|
|
/-- Internal exception identifier -/
|
|
structure InternalExceptionId where
|
|
idx : Nat := 0
|
|
deriving Inhabited, BEq
|
|
|
|
/-- Internal exceptions registered in the system. -/
|
|
builtin_initialize internalExceptionsRef : IO.Ref (Array Name) ← IO.mkRef #[]
|
|
|
|
/--
|
|
Register a new internal exception in the system.
|
|
Each internal exception has a unique index.
|
|
Throw an exception if the given name is not unique.
|
|
This method is usually invoked using the `initialize` command.
|
|
-/
|
|
def registerInternalExceptionId (name : Name) : IO InternalExceptionId := do
|
|
let exs ← internalExceptionsRef.get
|
|
if exs.contains name then throw <| IO.userError s!"invalid internal exception id, '{name}' has already been used"
|
|
let nextIdx := exs.size
|
|
internalExceptionsRef.modify fun a => a.push name
|
|
pure { idx := nextIdx }
|
|
|
|
/-- Convert internal exception id into the message "internal exception #<idx>"-/
|
|
def InternalExceptionId.toString (id : InternalExceptionId) : String :=
|
|
s!"internal exception #{id.idx}"
|
|
|
|
/-- Retrieve the name used to register the internal exception. -/
|
|
def InternalExceptionId.getName (id : InternalExceptionId) : IO Name := do
|
|
let exs ← internalExceptionsRef.get
|
|
let i := id.idx;
|
|
if h : i < exs.size then
|
|
return exs[i]
|
|
else
|
|
throw <| IO.userError "invalid internal exception id"
|
|
|
|
end Lean
|