style: refactor process to Lean 4 compiler style

DocGen4/Process/Analyze.lean

@@ -96,7 +96,7 @@ def getAllModuleDocs (relevantModules : Array Name) : MetaM (HashMap Name Module
     let moduleData := env.header.moduleData.get! modIdx
     let imports := moduleData.imports.map Import.module
     res := res.insert module <| Module.mk module modDocs imports
-  pure res
+  return res
 
 /--
 Run the doc-gen analysis on all modules that are loaded into the `Environment`
@@ -124,8 +124,8 @@ def process (task : AnalyzeTask) : MetaM (AnalyzerResult × Hierarchy) := do
         fileName := ← getFileName,
         fileMap := ← getFileMap
       }
-      let analysis := Prod.fst <$> Meta.MetaM.toIO (DocInfo.ofConstant (name, cinfo)) config { env := env } {} {}
-      if let some dinfo ← analysis then
+      let analysis ← Prod.fst <$> Meta.MetaM.toIO (DocInfo.ofConstant (name, cinfo)) config { env := env } {} {}
+      if let some dinfo := analysis then
         let moduleName := env.allImportedModuleNames.get! modidx
         let module := res.find! moduleName
         res := res.insert moduleName {module with members := module.members.push (ModuleMember.docInfo dinfo)}
@@ -142,7 +142,7 @@ def process (task : AnalyzeTask) : MetaM (AnalyzerResult × Hierarchy) := do
     moduleNames := allModules,
     moduleInfo := res,
   }
-  pure (analysis, hierarchy)
+  return (analysis, hierarchy)
 
 def filterMapDocInfo (ms : Array ModuleMember) : Array DocInfo :=
   ms.filterMap filter

DocGen4/Process/Attributes.lean

@@ -102,18 +102,18 @@ def parametricAttributes : Array ParametricAttrWrapper := #[⟨externAttr⟩,
 
 def getTags (decl : Name) : MetaM (Array String) := do
   let env ← getEnv
-  pure <| tagAttributes.filter (TagAttribute.hasTag · env decl) |>.map (λ t => t.attr.name.toString)
+  return tagAttributes.filter (TagAttribute.hasTag · env decl) |>.map (·.attr.name.toString)
 
 def getValuesAux {α : Type} {attrKind : Type → Type} [va : ValueAttr attrKind] [Inhabited α] [ToString α] (decl : Name) (attr : attrKind α) : MetaM (Option String) := do
   let env ← getEnv
-  pure <| va.getValue attr env decl
+  return va.getValue attr env decl
 
 def getValues {attrKind : Type → Type} [ValueAttr attrKind] (decl : Name) (attrs : Array (ValueAttrWrapper attrKind)) : MetaM (Array String) := do
   let mut res := #[]
   for attr in attrs do
     if let some val ← @getValuesAux attr.α attrKind _ attr.inhab attr.str decl attr.attr then
       res := res.push val
-  pure res
+  return res
 
 def getEnumValues (decl : Name) : MetaM (Array String) := getValues decl enumAttributes
 def getParametricValues (decl : Name) : MetaM (Array String) := getValues decl parametricAttributes
@@ -123,23 +123,21 @@ def getDefaultInstance (decl : Name) (className : Name) : MetaM (Option String)
   for (inst, prio) in insts do
     if inst == decl then
       return some s!"defaultInstance {prio}"
-  pure none
+  return none
 
 def hasSimp (decl : Name) : MetaM (Option String) := do
   let thms ← simpExtension.getTheorems
-  pure <|
   if thms.isLemma (.decl decl) then
-      some "simp"
+    return "simp"
   else
-      none
+    return none
 
 def hasCsimp (decl : Name) : MetaM (Option String) := do
   let env ← getEnv
-  pure <|
   if Compiler.hasCSimpAttribute env decl then
-      some "csimp"
+    return some "csimp"
   else
-      none
+    return none
 
 /--
 The list of custom attributes, that don't fit in the parametric or enum
@@ -152,7 +150,7 @@ def getCustomAttrs (decl : Name) : MetaM (Array String) := do
   for attr in customAttrs do
     if let some value ← attr decl then
       values := values.push value
-  pure values
+  return values
 
 /--
 The main entry point for recovering all attribute values for a given
@@ -163,6 +161,6 @@ def getAllAttributes (decl : Name) : MetaM (Array String) := do
   let enums ← getEnumValues decl
   let parametric ← getParametricValues decl
   let customs ← getCustomAttrs decl
-  pure <| customs ++ tags ++ enums ++ parametric
+  return customs ++ tags ++ enums ++ parametric
 
 end DocGen4

DocGen4/Process/AxiomInfo.lean

@@ -14,7 +14,7 @@ open Lean Meta
 
 def AxiomInfo.ofAxiomVal (v : AxiomVal) : MetaM AxiomInfo := do
   let info ← Info.ofConstantVal v.toConstantVal
-  pure {
+  return {
     toInfo := info,
     isUnsafe := v.isUnsafe
   } 

DocGen4/Process/Base.lean

@@ -177,9 +177,9 @@ def prettyPrintTerm (expr : Expr) : MetaM CodeWithInfos := do
     fileMap := default,
     ngen := ← getNGen
   }
-  pure <| tagCodeInfos ctx infos tt
+  return tagCodeInfos ctx infos tt
 
 def isInstance (declName : Name) : MetaM Bool := do
-  pure <| (instanceExtension.getState (←getEnv)).instanceNames.contains declName
+  return (instanceExtension.getState (← getEnv)).instanceNames.contains declName
 
 end DocGen4.Process

DocGen4/Process/DefinitionInfo.lean

@@ -33,7 +33,7 @@ def valueToEq (v : DefinitionVal) : MetaM Expr := withLCtx {} {} do
       let us := v.levelParams.map mkLevelParam
       let type ← mkEq (mkAppN (Lean.mkConst v.name us) xs) body
       let type ← mkForallFVars xs type
-      pure type
+      return type
 
 def DefinitionInfo.ofDefinitionVal (v : DefinitionVal) : MetaM DefinitionInfo := do
   let info ← Info.ofConstantVal v.toConstantVal
@@ -44,7 +44,7 @@ def DefinitionInfo.ofDefinitionVal (v : DefinitionVal) : MetaM DefinitionInfo :=
     match eqs? with
     | some eqs =>
       let equations ← eqs.mapM processEq
-      pure {
+      return {
         toInfo := info,
         isUnsafe,
         hints := v.hints,
@@ -53,7 +53,7 @@ def DefinitionInfo.ofDefinitionVal (v : DefinitionVal) : MetaM DefinitionInfo :=
       }
     | none =>
       let equations := #[← prettyPrintTerm <| stripArgs (← valueToEq v)]
-      pure {
+      return {
         toInfo := info,
         isUnsafe,
         hints := v.hints,
@@ -62,7 +62,7 @@ def DefinitionInfo.ofDefinitionVal (v : DefinitionVal) : MetaM DefinitionInfo :=
       }
   catch err =>
     IO.println s!"WARNING: Failed to calculate equational lemmata for {v.name}: {← err.toMessageData.toString}"
-    pure {
+    return {
       toInfo := info,
       isUnsafe,
       hints := v.hints,

DocGen4/Process/DocInfo.lean

@@ -108,7 +108,7 @@ def isBlackListed (declName : Name) : MetaM Bool := do
     <||> isRec declName
     <||> isMatcher declName
   -- TODO: Evaluate whether filtering out declarations without range is sensible
-  | none => pure true
+  | none => return true
 
 -- TODO: Is this actually the best way?
 def isProjFn (declName : Name) : MetaM Bool := do
@@ -119,44 +119,44 @@ def isProjFn (declName : Name) : MetaM Bool := do
       match getStructureInfo? env parent with
       | some i =>
         match i.fieldNames.find? (· == name) with
-        | some _ => pure true
-        | none => pure false
+        | some _ => return true
+        | none => return false
       | none => panic! s!"{parent} is not a structure"
     else
-      pure false
-  | _ => pure false
+      return false
+  | _ => return false
 
-def ofConstant : (Name × ConstantInfo) → MetaM (Option DocInfo) := λ (name, info) => do
-  if (←isBlackListed name) then
+def ofConstant : (Name × ConstantInfo) → MetaM (Option DocInfo) := fun (name, info) => do
+  if ← isBlackListed name then
     return none
   match info with
-  | ConstantInfo.axiomInfo i => pure <| some <| axiomInfo (←AxiomInfo.ofAxiomVal i)
-  | ConstantInfo.thmInfo i => pure <| some <| theoremInfo (←TheoremInfo.ofTheoremVal i)
-  | ConstantInfo.opaqueInfo i => pure <| some <| opaqueInfo (←OpaqueInfo.ofOpaqueVal i)
+  | ConstantInfo.axiomInfo i => return some <| axiomInfo (← AxiomInfo.ofAxiomVal i)
+  | ConstantInfo.thmInfo i => return some <| theoremInfo (← TheoremInfo.ofTheoremVal i)
+  | ConstantInfo.opaqueInfo i => return some <| opaqueInfo (← OpaqueInfo.ofOpaqueVal i)
   | ConstantInfo.defnInfo i =>
     if ← isProjFn i.name then
-      pure none
+      return none
     else
       if ← isInstance i.name then
         let info ← InstanceInfo.ofDefinitionVal i
-        pure <| some <| instanceInfo info
+        return some <| instanceInfo info
       else
         let info ← DefinitionInfo.ofDefinitionVal i
-        pure <| some <| definitionInfo  info
+        return some <| definitionInfo  info
   | ConstantInfo.inductInfo i =>
     let env ← getEnv
     if isStructure env i.name then
       if isClass env i.name then
-        pure <| some <| classInfo (←ClassInfo.ofInductiveVal i)
+        return some <| classInfo (← ClassInfo.ofInductiveVal i)
       else
-        pure <| some <| structureInfo (←StructureInfo.ofInductiveVal i)
+        return some <| structureInfo (← StructureInfo.ofInductiveVal i)
     else
       if isClass env i.name then
-        pure <| some <| classInductiveInfo (←ClassInductiveInfo.ofInductiveVal i)
+        return some <| classInductiveInfo (← ClassInductiveInfo.ofInductiveVal i)
       else
-        pure <| some <| inductiveInfo (←InductiveInfo.ofInductiveVal i)
+        return some <| inductiveInfo (← InductiveInfo.ofInductiveVal i)
   -- we ignore these for now
-  | ConstantInfo.ctorInfo _ | ConstantInfo.recInfo _ | ConstantInfo.quotInfo _ => pure none
+  | ConstantInfo.ctorInfo _ | ConstantInfo.recInfo _ | ConstantInfo.quotInfo _ => return none
 
 def getKindDescription : DocInfo → String
 | axiomInfo i => if i.isUnsafe then "unsafe axiom" else "axiom"
@@ -168,7 +168,7 @@ def getKindDescription : DocInfo → String
   | DefinitionSafety.partial => "partial def"
 | definitionInfo i => Id.run do
   if i.hints.isAbbrev then
-    pure "abbrev"
+    return "abbrev"
   else
     let mut modifiers := #[]
     if i.isUnsafe then
@@ -177,7 +177,7 @@ def getKindDescription : DocInfo → String
       modifiers := modifiers.push "noncomputable"
 
     modifiers := modifiers.push "def"
-    pure <| String.intercalate " " modifiers.toList
+    return String.intercalate " " modifiers.toList
 | instanceInfo i => Id.run do
   let mut modifiers := #[]
   if i.isUnsafe then
@@ -186,7 +186,7 @@ def getKindDescription : DocInfo → String
     modifiers := modifiers.push "noncomputable"
 
   modifiers := modifiers.push "instance"
-  pure <| String.intercalate " " modifiers.toList
+  return String.intercalate " " modifiers.toList
 | inductiveInfo i => if i.isUnsafe then "unsafe inductive" else "inductive"
 | structureInfo _ => "structure"
 | classInfo _ => "class"

DocGen4/Process/Hierarchy.lean

@@ -18,11 +18,11 @@ def getNLevels (name : Name) (levels: Nat) : Name :=
   (components.drop (components.length - levels)).reverse.foldl (· ++ ·) Name.anonymous
 
 inductive Hierarchy where
-| node (name : Name) (isFile : Bool) (children : RBNode Name (λ _ => Hierarchy)) : Hierarchy
+| node (name : Name) (isFile : Bool) (children : RBNode Name (fun _ => Hierarchy)) : Hierarchy
 
 instance : Inhabited Hierarchy := ⟨Hierarchy.node Name.anonymous false RBNode.leaf⟩
 
-abbrev HierarchyMap := RBNode Name (λ _ => Hierarchy)
+abbrev HierarchyMap := RBNode Name (fun _ => Hierarchy)
 
 -- Everything in this namespace is adapted from stdlib's RBNode
 namespace HierarchyMap
@@ -101,11 +101,11 @@ def baseDirBlackList : HashSet String :=
 partial def fromDirectoryAux (dir : System.FilePath) (previous : Name) : IO (Array Name) := do
   let mut children := #[]
   for entry in ← System.FilePath.readDir dir do
-    if (←entry.path.isDir) then
+    if ← entry.path.isDir then
       children := children ++ (← fromDirectoryAux entry.path (.str previous entry.fileName))
     else if entry.path.extension = some "html" then
       children := children.push <| .str previous (entry.fileName.dropRight ".html".length)
-  pure children
+  return children
 
 def fromDirectory (dir : System.FilePath) : IO Hierarchy := do
     let mut children := #[]
@@ -116,7 +116,7 @@ def fromDirectory (dir : System.FilePath) : IO Hierarchy := do
         children := children ++ (← fromDirectoryAux entry.path (.mkSimple entry.fileName))
       else if entry.path.extension = some "html" then
         children := children.push <| .mkSimple (entry.fileName.dropRight ".html".length)
-    pure <| Hierarchy.fromArray children
+    return Hierarchy.fromArray children
 
 end Hierarchy
 end DocGen4

DocGen4/Process/InductiveInfo.lean

@@ -20,8 +20,8 @@ def getConstructorType (ctor : Name) : MetaM Expr := do
 
 def InductiveInfo.ofInductiveVal (v : InductiveVal) : MetaM InductiveInfo := do
   let info ← Info.ofConstantVal v.toConstantVal
-  let ctors ← v.ctors.mapM (λ name => do NameInfo.ofTypedName name (←getConstructorType name))
-  pure {
+  let ctors ← v.ctors.mapM (fun name => do NameInfo.ofTypedName name (← getConstructorType name))
+  return {
     toInfo := info,
     ctors,
     isUnsafe := v.isUnsafe

DocGen4/Process/InstanceInfo.lean

@@ -24,7 +24,7 @@ where
     | .sort .zero => modify (·.push "_builtin_prop")
     | .sort (.succ _) => modify (·.push "_builtin_typeu")
     | .sort _ => modify (·.push "_builtin_sortu")
-    | _ => pure ()
+    | _ => return ()
 
 def InstanceInfo.ofDefinitionVal (v : DefinitionVal) : MetaM InstanceInfo := do
   let mut info ← DefinitionInfo.ofDefinitionVal v
@@ -32,7 +32,6 @@ def InstanceInfo.ofDefinitionVal (v : DefinitionVal) : MetaM InstanceInfo := do
   if let some instAttr ← getDefaultInstance v.name className then
     info := { info with attrs := info.attrs.push instAttr }
   let typeNames ← getInstanceTypes v.type
-
   return {
     toDefinitionInfo := info,
     className,

DocGen4/Process/NameInfo.lean

@@ -13,15 +13,15 @@ open Lean Meta
 
 def NameInfo.ofTypedName (n : Name) (t : Expr) : MetaM NameInfo := do
   let env ← getEnv
-  pure { name := n, type := ←prettyPrintTerm t, doc := ←findDocString? env n}
+  return { name := n, type := ← prettyPrintTerm t, doc := ← findDocString? env n}
 
 partial def typeToArgsType (e : Expr) : (Array (Name × Expr × BinderInfo) × Expr) :=
-  let helper := λ name type body data =>
+  let helper := fun name type body data =>
     -- Once we hit a name with a macro scope we stop traversing the expression
     -- and print what is left after the : instead. The only exception
     -- to this is instances since these almost never have a name
     -- but should still be printed as arguments instead of after the :.
-    if name.hasMacroScopes ∧ ¬data.isInstImplicit then
+    if name.hasMacroScopes && !data.isInstImplicit then
       (#[], e)
     else
       let name := name.eraseMacroScopes
@@ -35,15 +35,15 @@ partial def typeToArgsType (e : Expr) : (Array (Name × Expr × BinderInfo) × E
 
 def Info.ofConstantVal (v : ConstantVal) : MetaM Info := do
   let (args, type) := typeToArgsType v.type
-  let args ← args.mapM (λ (n, e, b) => do pure <| Arg.mk n (←prettyPrintTerm e) b)
+  let args ← args.mapM (fun (n, e, b) => do return Arg.mk n (← prettyPrintTerm e) b)
   let nameInfo ← NameInfo.ofTypedName v.name type
   match ← findDeclarationRanges? v.name with
   -- TODO: Maybe selection range is more relevant? Figure this out in the future
-  | some range => pure {
+  | some range => return {
       toNameInfo := nameInfo,
       args,
       declarationRange := range.range,
-      attrs := (←getAllAttributes v.name)
+      attrs := ← getAllAttributes v.name
     }
   | none => panic! s!"{v.name} is a declaration without position"
 

DocGen4/Process/OpaqueInfo.lean

@@ -24,7 +24,7 @@ def OpaqueInfo.ofOpaqueVal (v : OpaqueVal) : MetaM OpaqueInfo := do
       DefinitionSafety.unsafe
     else
       DefinitionSafety.safe
-  pure {
+  return {
     toInfo := info,
     value,
     definitionSafety

DocGen4/Process/StructureInfo.lean

@@ -20,7 +20,7 @@ def dropArgs (type : Expr) (n : Nat) : (Expr × List (Name × Expr)) :=
     let body := body.instantiate1 <| mkFVar ⟨name⟩
     let next := dropArgs body x
     { next with snd := (name, type) :: next.snd}
-  | _e, _x + 1 => panic! s!"No forallE left"
+  | _, _ + 1 => panic! s!"No forallE left"
 
 def getFieldTypes (struct : Name) (ctor : ConstructorVal) (parents : Nat) : MetaM (Array NameInfo) := do
   let type := ctor.type
@@ -29,7 +29,7 @@ def getFieldTypes (struct : Name) (ctor : ConstructorVal) (parents : Nat) : Meta
   let mut fieldInfos := #[]
   for (name, type) in fields do
     fieldInfos := fieldInfos.push <| ← NameInfo.ofTypedName (struct.append name) type
-  pure <| fieldInfos
+  return fieldInfos
 
 def StructureInfo.ofInductiveVal (v : InductiveVal) : MetaM StructureInfo := do
   let info ← Info.ofConstantVal v.toConstantVal
@@ -40,14 +40,14 @@ def StructureInfo.ofInductiveVal (v : InductiveVal) : MetaM StructureInfo := do
   match getStructureInfo? env v.name with
   | some i =>
     if i.fieldNames.size - parents.size > 0 then
-      pure {
+      return {
         toInfo := info,
-        fieldInfo := (←getFieldTypes v.name ctorVal parents.size),
+        fieldInfo := ← getFieldTypes v.name ctorVal parents.size,
         parents,
         ctor
       }
     else
-      pure {
+      return {
         toInfo := info,
         fieldInfo := #[],
         parents,

DocGen4/Process/TheoremInfo.lean

@@ -14,6 +14,6 @@ open Lean Meta
 
 def TheoremInfo.ofTheoremVal (v : TheoremVal) : MetaM TheoremInfo := do
   let info ← Info.ofConstantVal v.toConstantVal
-  pure { toInfo := info }
+  return { toInfo := info }
 
 end DocGen4.Process

Main.lean

@@ -8,7 +8,7 @@ def getTopLevelModules (p : Parsed) : IO (List String) :=  do
   let topLevelModules := p.variableArgsAs! String |>.toList
   if topLevelModules.length == 0 then
     throw <| IO.userError "No topLevelModules provided."
-  pure topLevelModules
+  return topLevelModules
 
 def runSingleCmd (p : Parsed) : IO UInt32 := do
   let relevantModules := [p.positionalArg! "module" |>.as! String |> String.toName]
@@ -19,14 +19,14 @@ def runSingleCmd (p : Parsed) : IO UInt32 := do
     IO.println "Outputting HTML"
     let baseConfig := getSimpleBaseContext hierarchy
     htmlOutputResults baseConfig doc ws (p.hasFlag "ink")
-    pure 0
+    return 0
   | Except.error rc => pure rc
 
 def runIndexCmd (_p : Parsed) : IO UInt32 := do
   let hierarchy ← Hierarchy.fromDirectory Output.basePath
   let baseConfig := getSimpleBaseContext hierarchy
   htmlOutputIndex baseConfig
-  pure 0
+  return 0
 
 def runGenCoreCmd (_p : Parsed) : IO UInt32 := do
   let res ← lakeSetup
@@ -36,7 +36,7 @@ def runGenCoreCmd (_p : Parsed) : IO UInt32 := do
     IO.println "Outputting HTML"
     let baseConfig := getSimpleBaseContext hierarchy
     htmlOutputResults baseConfig doc ws (ink := False) 
-    pure 0
+    return 0
   | Except.error rc => pure rc
 
 def runDocGenCmd (_p : Parsed) : IO UInt32 := do