structure Lean.Language.Snapshot.Diagnostics : Type

MessageLog with interactive diagnostics.

Can be created using Diagnostics.empty or Diagnostics.ofMessageLog.

• msgLog : MessageLog

  Non-interactive message log.

• interactiveDiagsRef? : Option (IO.Ref (Option Dynamic))

  Dynamic mutable slot usable by the language server for memorizing interactive diagnostics. If none, interactive diagnostics are not remembered, which should only be used for messages not containing any interactive elements as client-side state will be lost on recreating a diagnostic.

  See also section "Communication" in Lean/Server/README.md.

instance Lean.Language.Snapshot.instInhabitedDiagnostics : Inhabited Diagnostics

def Lean.Language.Snapshot.Diagnostics.empty : Diagnostics

The empty set of diagnostics.

structure Lean.Language.Snapshot : Type

The base class of all snapshots: all the generic information the language server needs about a snapshot.

• desc : String

  Debug description shown by trace.Elab.snapshotTree, defaults to the caller's decl name.

• diagnostics : Diagnostics

  The messages produced by this step. The union of message logs of all finished snapshots is reported to the user.

• infoTree? : Option Elab.InfoTree

  General elaboration metadata produced by this step.

• traces : TraceState

  Trace data produced by this step. Currently used only by trace.profiler.output, otherwise we depend on the elaborator adding traces to diagnostics eventually.

• isFatal : Bool

  Whether it should be indicated to the user that a fatal error (which should be part of diagnostics) occurred that prevents processing of the remainder of the file.

instance Lean.Language.instInhabitedSnapshot : Inhabited Snapshot

def Lean.Language.SnapshotTask.defaultReportingRange? (stx? : Option Syntax) : Option String.Range

Yields the default reporting range of a Syntax, which is just the canonicalOnly range of the syntax.

structure Lean.Language.SnapshotTask (α : Type) : Type

A task producing some snapshot type (usually a subclass of Snapshot).

• stx? : Option Syntax

  Syntax processed by this SnapshotTask. The Syntax is used by the language server to determine whether to force this SnapshotTask when a request is made. In general, the elaborator retains the following invariant: If stx? is none, then this snapshot task (and all of its children) do not contain InfoTree information that can be used in the language server, and so the language server will ignore it when it is looking for an InfoTree. Nonetheless, if stx? is none, then this snapshot task (and any of its children) may still contain message log information.

• reportingRange? : Option String.Range

  Range that is marked as being processed by the server while the task is running. If none, the range of the outer task if some or else the entire file is reported.

• cancelTk? : Option IO.CancelToken

  Cancellation token that can be set by the server to cancel the task when it detects the results are not needed anymore.

• task : Task α

  Underlying task producing the snapshot.

instance Lean.Language.instNonemptySnapshotTask {α✝ : Type} [Nonempty α✝] : Nonempty (SnapshotTask α✝)

instance Lean.Language.instInhabitedSnapshotTask {a✝ : Type} [Inhabited a✝] : Inhabited (SnapshotTask a✝)

def Lean.Language.SnapshotTask.ofIO {α : Type} (stx? : Option Syntax) (cancelTk? : Option IO.CancelToken) (reportingRange? : Option String.Range := defaultReportingRange? stx?) (act : BaseIO α) : BaseIO (SnapshotTask α)

Creates a snapshot task from the syntax processed by the task and a BaseIO action.

def Lean.Language.SnapshotTask.finished {α : Type} (stx? : Option Syntax) (a : α) : SnapshotTask α

Creates a finished snapshot task.

def Lean.Language.SnapshotTask.map {α β : Type} (t : SnapshotTask α) (f : α → β) (stx? : Option Syntax := t.stx?) (reportingRange? : Option String.Range := t.reportingRange?) (sync : Bool := false) : SnapshotTask β

Transforms a task's output without changing the processed syntax.

def Lean.Language.SnapshotTask.bindIO {α β : Type} (t : SnapshotTask α) (act : α → BaseIO (SnapshotTask β)) (stx? : Option Syntax := t.stx?) (reportingRange? : Option String.Range := t.reportingRange?) (cancelTk? : Option IO.CancelToken) (sync : Bool := false) : BaseIO (SnapshotTask β)

Chains two snapshot tasks. The processed syntax and the reporting range are taken from the first task if not specified; the processed syntax and the reporting range of the second task are discarded. The cancellation tokens of both tasks are discarded. They are replaced with the given token if any.

def Lean.Language.SnapshotTask.get {α : Type} (t : SnapshotTask α) : α

Synchronously waits on the result of the task.

def Lean.Language.SnapshotTask.get? {α : Type} (t : SnapshotTask α) : BaseIO (Option α)

Returns task result if already finished or else none.

structure Lean.Language.SyntaxGuarded (α : Type) : Type

Arbitrary value paired with a syntax that should be inspected when considering the value for reuse.

• stx : Syntax

  Syntax to be inspected for reuse.

• val : α

  Potentially reusable value.

structure Lean.Language.SnapshotBundle (α : Type) : Type

Pair of (optional) old snapshot task usable for incremental reuse and new snapshot promise for incremental reporting. Inside the elaborator, we build snapshots by carrying such bundles and then checking if we can reuse old? if set or else redoing the corresponding elaboration step. In either case, we derive new bundles for nested snapshots, if any, and finally resolve new to the result.

Note that failing to resolve a created promise will block the language server indefinitely! We use withAlwaysResolvedPromise/withAlwaysResolvedPromises to ensure this doesn't happen.

In the future, the 1-element history old? may be replaced with a global cache indexed by strong hashes but the promise will still need to be passed through the elaborator.

• old? : Option (SyntaxGuarded (SnapshotTask α))

  Snapshot task of corresponding elaboration in previous document version if any, paired with its old syntax to be considered for reuse. Should be set to none as soon as reuse can be ruled out.

• new : IO.Promise α

  Promise of snapshot value for the current document. When resolved, the language server will report its result even before the current elaborator invocation has finished.

structure Lean.Language.SnapshotTree : Type

Tree of snapshots where each snapshot comes with an array of asynchronous further subtrees. Used for asynchronously collecting information about the entirety of snapshots in the language server. The involved tasks may form a DAG on the Task dependency level but this is not captured by this data structure.

• element : Snapshot

  The immediately available element of the snapshot tree node.

• children : Array (SnapshotTask SnapshotTree)

  The asynchronously available children of the snapshot tree node.

instance Lean.Language.instInhabitedSnapshotTree : Inhabited SnapshotTree

instance Lean.Language.instTypeNameSnapshotTree : TypeName SnapshotTree

class Lean.Language.ToSnapshotTree (α : Type) : Type

Helper class for projecting a heterogeneous hierarchy of snapshot classes to a homogeneous representation.

• toSnapshotTree : α → SnapshotTree

  Transforms a language-specific snapshot to a homogeneous snapshot tree.

instance Lean.Language.instToSnapshotTreeSnapshotTree : ToSnapshotTree SnapshotTree

instance Lean.Language.instToSnapshotTreeOption {α : Type} [ToSnapshotTree α] : ToSnapshotTree (Option α)

partial def Lean.Language.SnapshotTask.cancelRec {α : Type} [ToSnapshotTree α] (t : SnapshotTask α) : BaseIO Unit

Recursively triggers all SnapshotTask.cancelTk? in the reachable tree, asynchronously.

structure Lean.Language.SnapshotLeafextends Lean.Language.Snapshot : Type

Snapshot type without child nodes.

• desc : String
• diagnostics : Diagnostics
• infoTree? : Option Elab.InfoTree
• traces : TraceState
• isFatal : Bool

instance Lean.Language.instNonemptySnapshotLeaf : Nonempty SnapshotLeaf

instance Lean.Language.instTypeNameSnapshotLeaf : TypeName SnapshotLeaf

instance Lean.Language.instToSnapshotTreeSnapshotLeaf : ToSnapshotTree SnapshotLeaf

structure Lean.Language.DynamicSnapshot : Type

Arbitrary snapshot type, used for extensibility.

• val : Dynamic

  Concrete snapshot value as Dynamic.

• tree : Thunk SnapshotTree

  Snapshot tree retrieved from val before erasure. We do thunk even the first level as accessing it too early can create some unnecessary tasks from toSnapshotTree that are otherwise avoided by (sync := true) when accessing only after elaboration has finished. Early access can even lead to deadlocks when later forcing these unnecessary tasks on a starved thread pool.

instance Lean.Language.instToSnapshotTreeDynamicSnapshot : ToSnapshotTree DynamicSnapshot

def Lean.Language.DynamicSnapshot.ofTyped {α : Type} [TypeName α] [ToSnapshotTree α] (val : α) : DynamicSnapshot

Creates a DynamicSnapshot from a typed snapshot value.

def Lean.Language.DynamicSnapshot.toTyped? (α : Type) [TypeName α] (snap : DynamicSnapshot) : Option α

Returns the original snapshot value if it is of the given type.

instance Lean.Language.instInhabitedDynamicSnapshot : Inhabited DynamicSnapshot

@[specialize #[]]

partial def Lean.Language.SnapshotTree.forM {m : Type u_1 → Type u_2} [Monad m] (s : SnapshotTree) (f : Snapshot → m PUnit) : m PUnit

Runs a tree of snapshots to conclusion, incrementally performing f on each snapshot in tree preorder.

@[specialize #[]]

partial def Lean.Language.SnapshotTree.foldM {m : Type u_1 → Type u_2} {α : Type u_1} [Monad m] (s : SnapshotTree) (f : α → Snapshot → m α) (init : α) : m α

Runs a tree of snapshots to conclusion, folding the function f over each snapshot in tree preorder.

opaque Lean.Language.printMessageEndPos : Lean.Option Bool

Option for printing end position of each message in addition to start position. Used for testing message ranges in the test suite.

def Lean.Language.reportMessages (msgLog : MessageLog) (opts : Options) (json : Bool := false) (severityOverrides : NameMap MessageSeverity := ∅) : IO Bool

Reports messages on stdout and returns whether an error was reported. If json is true, prints messages as JSON (one per line). If a message's kind is in severityOverrides, it will be reported with the specified severity.

def Lean.Language.SnapshotTree.runAndReport (s : SnapshotTree) (opts : Options) (json : Bool := false) (severityOverrides : NameMap MessageSeverity := ∅) : IO Bool

Runs a tree of snapshots to conclusion and incrementally report messages on stdout. Messages are reported in tree preorder. Returns whether any errors were reported. This function is used by the cmdline driver; see Lean.Server.FileWorker.reportSnapshots for how the language server reports snapshots asynchronously.

def Lean.Language.SnapshotTree.getAll (s : SnapshotTree) : Array Snapshot

Waits on and returns all snapshots in the tree.

def Lean.Language.SnapshotTree.waitAll : SnapshotTree → BaseIO (Task Unit)

Returns a task that waits on all snapshots in the tree.

partial def Lean.Language.SnapshotTree.waitAll.go : List (SnapshotTask SnapshotTree) → BaseIO (Task Unit)

structure Lean.Language.ProcessingContextextends Lean.Parser.InputContext : Type

Context of an input processing invocation.

• input : String
• fileName : String
• fileMap : FileMap

@[reducible, inline]

abbrev Lean.Language.ProcessingT (m : Type → Type u_1) (α : Type) : Type u_1

Monad transformer holding all relevant data for processing.

@[reducible, inline]

abbrev Lean.Language.ProcessingM (α : Type) : Type

Monad holding all relevant data for processing.

instance Lean.Language.instMonadLiftProcessingMProcessingTIO : MonadLift ProcessingM (ProcessingT IO)

def Lean.Language.Snapshot.Diagnostics.ofMessageLog (msgLog : MessageLog) : BaseIO Diagnostics

Creates snapshot message log from non-interactive message log, also allocating a mutable cell that can be used by the server to memorize interactive diagnostics derived from the log.

def Lean.Language.diagnosticsOfHeaderError (msg : String) : ProcessingM Snapshot.Diagnostics

Creates diagnostics from a single error message that should span the whole file.

def Lean.Language.withHeaderExceptions {α : Type} (ex : Snapshot → α) (act : ProcessingT IO α) : ProcessingM α

Adds unexpected exceptions from header processing to the message log as a last resort; standard errors should already have been caught earlier.

def Lean.Language.mkIncrementalProcessor {InitSnap : Type} (process : Option InitSnap → ProcessingM InitSnap) : BaseIO (Parser.InputContext → BaseIO InitSnap)

Builds a function for processing a language using incremental snapshots by passing the previous snapshot to Language.process on subsequent invocations.