FunctionType class Null safety

The type of a function, method, constructor, getter, or setter. Function types come in three variations:

  • The types of functions that only have required parameters. These have the general form (T1, …, Tn) → T.
  • The types of functions with optional positional parameters. These have the general form (T1, …, Tn, T<sub>n+1</sub> &hellip;, T<sub>n+k</sub>) → T.
  • The types of functions with named parameters. These have the general form (T1, …, Tn, {Tx1 x1, …, Txk xk}) → T.

Clients may not extend, implement or mix-in this class.

Implemented types

Constructors

FunctionType()

Properties

alias → InstantiatedTypeAliasElement?
If this type is an instantiation of a type alias, information about the alias element, and the type arguments. Otherwise return null.
read-onlyinherited
element → Null
Return the element representing the declaration of this type, or null if the type is not associated with an element.
read-onlyoverride
element2 → Null
Return the element representing the declaration of this type, or null if the type is not associated with an element.
read-onlyoverride
hashCode → int
The hash code for this object.
read-onlyinherited
isBottom → bool
Return true if this type represents the bottom type.
read-onlyinherited
isDartAsyncFuture → bool
Return true if this type represents the type 'Future' defined in the dart:async library.
read-onlyinherited
isDartAsyncFutureOr → bool
Return true if this type represents the type 'FutureOr
read-onlyinherited
isDartAsyncStream → bool
Return true if this type represents the type 'Stream' defined in the dart:async library.
read-onlyinherited
isDartCoreBool → bool
Return true if this type represents the type 'bool' defined in the dart:core library.
read-onlyinherited
isDartCoreDouble → bool
Return true if this type represents the type 'double' defined in the dart:core library.
read-onlyinherited
isDartCoreEnum → bool
Return true if this type represents the type 'Enum' defined in the dart:core library.
read-onlyinherited
isDartCoreFunction → bool
Return true if this type represents the type 'Function' defined in the dart:core library.
read-onlyinherited
isDartCoreInt → bool
Return true if this type represents the type 'int' defined in the dart:core library.
read-onlyinherited
isDartCoreIterable → bool
Returns true if this type represents the type 'Iterable' defined in the dart:core library.
read-onlyinherited
isDartCoreList → bool
Returns true if this type represents the type 'List' defined in the dart:core library.
read-onlyinherited
isDartCoreMap → bool
Returns true if this type represents the type 'Map' defined in the dart:core library.
read-onlyinherited
isDartCoreNull → bool
Return true if this type represents the type 'Null' defined in the dart:core library.
read-onlyinherited
isDartCoreNum → bool
Return true if this type represents the type 'num' defined in the dart:core library.
read-onlyinherited
isDartCoreObject → bool
Return true if this type represents the type Object defined in the dart:core library.
read-onlyinherited
isDartCoreRecord → bool
Return true if this type represents the type 'Record' defined in the dart:core library.
read-onlyinherited
isDartCoreSet → bool
Returns true if this type represents the type 'Set' defined in the dart:core library.
read-onlyinherited
isDartCoreString → bool
Return true if this type represents the type 'String' defined in the dart:core library.
read-onlyinherited
isDartCoreSymbol → bool
Returns true if this type represents the type 'Symbol' defined in the dart:core library.
read-onlyinherited
isDynamic → bool
Return true if this type represents the type 'dynamic'.
read-onlyinherited
isVoid → bool
Return true if this type represents the type 'void'.
read-onlyinherited
name → String?
Return the name of this type, or null if the type does not have a name, such as when the type represents the type of an unnamed function.
read-onlyinherited
namedParameterTypes → Map<String, DartType>
Return a map from the names of named parameters to the types of the named parameters of this type of function. The entries in the map will be iterated in the same order as the order in which the named parameters were defined. If there were no named parameters declared then the map will be empty.
read-only
normalParameterNames → List<String>
The names of the required positional parameters of this type of function, in the order that the parameters appear.
read-only
normalParameterTypes → List<DartType>
Return a list containing the types of the normal parameters of this type of function. The parameter types are in the same order as they appear in the declaration of the function.
read-only
nullabilitySuffix → NullabilitySuffix
Return the nullability suffix of this type.
read-onlyinherited
optionalParameterNames → List<String>
The names of the optional positional parameters of this type of function, in the order that the parameters appear.
read-only
optionalParameterTypes → List<DartType>
Return a map from the names of optional (positional) parameters to the types of the optional parameters of this type of function. The entries in the map will be iterated in the same order as the order in which the optional parameters were defined. If there were no optional parameters declared then the map will be empty.
read-only
parameters → List<ParameterElement>
Return a list containing the parameters elements of this type of function. The parameter types are in the same order as they appear in the declaration of the function.
read-only
returnType → DartType
Return the type of object returned by this type of function.
read-only
runtimeType → Type
A representation of the runtime type of the object.
read-onlyinherited
typeFormals → List<TypeParameterElement>
The formal type parameters of this generic function. For example <T> T -> T.
read-only

Methods

accept<R>(TypeVisitor<R> visitor) → R
Use the given visitor to visit this type.
inherited
acceptWithArgument<R, A>(TypeVisitorWithArgument<R, A> visitor, A argument) → R
Use the given visitor to visit this type.
inherited
asInstanceOf(InterfaceElement element) → InterfaceType?
Return the canonical interface that this type implements for element, or null if such an interface does not exist.
inherited
getDisplayString({required bool withNullability}) → String
Return the presentation of this type as it should appear when presented to users in contexts such as error messages.
inherited
instantiate(List<DartType> argumentTypes) → FunctionType
Produces a new function type by substituting type parameters of this function type with the given argumentTypes. The resulting function type will have no type parameters.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed.
inherited
resolveToBound(DartType objectType) → DartType
If this type is a TypeParameterType, returns its bound if it has one, or objectType otherwise.
inherited
toString() → String
A string representation of this object.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
inherited