structure Lean.ProjectionFunctionInfo : Type

Given a structure S, Lean automatically creates an auxiliary definition (projection function) for each field. This structure caches information about these auxiliary definitions.

• ctorName : Name

  Constructor associated with the auxiliary projection function.

• numParams : Nat

  Number of parameters in the structure

• i : Nat

  The field index associated with the auxiliary projection function.

• fromClass : Bool

  true if the structure is a class.

@[implicit_reducible]

instance Lean.instInhabitedProjectionFunctionInfo : Inhabited ProjectionFunctionInfo

def Lean.instInhabitedProjectionFunctionInfo.default : ProjectionFunctionInfo

def Lean.instReprProjectionFunctionInfo.repr : ProjectionFunctionInfo → Nat → Format

@[implicit_reducible]

instance Lean.instReprProjectionFunctionInfo : Repr ProjectionFunctionInfo

@[export lean_mk_projection_info]

def Lean.mkProjectionInfoEx (ctorName : Name) (numParams i : Nat) (fromClass : Bool) : ProjectionFunctionInfo

@[export lean_projection_info_from_class]

def Lean.ProjectionFunctionInfo.fromClassEx (info : ProjectionFunctionInfo) : Bool

opaque Lean.projectionFnInfoExt : MapDeclarationExtension ProjectionFunctionInfo

def Lean.addProjectionFnInfo (env : Environment) (projName ctorName : Name) (numParams i : Nat) (fromClass : Bool) : Environment

def Lean.Environment.getProjectionFnInfo? (env : Environment) (projName : Name) : Option ProjectionFunctionInfo

def Lean.Environment.isProjectionFn (env : Environment) (declName : Name) : Bool

def Lean.Environment.getProjectionStructureName? (env : Environment) (projName : Name) : Option Name

If projName is the name of a projection function, return the associated structure name

def Lean.isProjectionFn {m : Type → Type} [MonadEnv m] [Monad m] (declName : Name) : m Bool

def Lean.getProjectionFnInfo? {m : Type → Type} [MonadEnv m] [Monad m] (declName : Name) : m (Option ProjectionFunctionInfo)

structure Lean.AuxParentProjectionInfo : Type

Auxiliary parent projection created when a parent structure cannot be represented as a subobject (e.g., due to diamond inheritance). Unlike regular projections, these construct the parent value from individual fields rather than extracting a single field. Example: AddMonoid'.toAddZero' when AddZero' cannot be a subobject of AddMonoid'.

• numParams : Nat

  Number of parameters in the child structure.

• fromClass : Bool

  true if the child structure is a class.

def Lean.instInhabitedAuxParentProjectionInfo.default : AuxParentProjectionInfo

@[implicit_reducible]

instance Lean.instInhabitedAuxParentProjectionInfo : Inhabited AuxParentProjectionInfo

@[implicit_reducible]

instance Lean.instReprAuxParentProjectionInfo : Repr AuxParentProjectionInfo

def Lean.instReprAuxParentProjectionInfo.repr : AuxParentProjectionInfo → Nat → Format

opaque Lean.auxParentProjInfoExt : MapDeclarationExtension AuxParentProjectionInfo

def Lean.addAuxParentProjectionInfo (env : Environment) (projName : Name) (numParams : Nat) (fromClass : Bool) : Environment

def Lean.Environment.getAuxParentProjectionInfo? (env : Environment) (projName : Name) : Option AuxParentProjectionInfo

def Lean.getAuxParentProjectionInfo? {m : Type → Type} [MonadEnv m] [Monad m] (declName : Name) : m (Option AuxParentProjectionInfo)