ScopeKey<T> class

The only purpose of ScopeKeys is to be globally unique so that they can be used to uniquely identify injected values. ScopeKeys are opaque – you are not supposed to read any other information from them except t heir identity.

You must NOT extend or implement this class.

The debugName is only used in error messages. We recommend that you use a debugName of the form: package_name.library_name.variableName

If a key is created with a default value, it will be returned by use when no value was provided for this key. null is a valid default value, provided the T is nullable (e.g. String?), and is distinct from no value.

The type argument T is used to infer the return type of use.

ScopeKey<int> countKey = ScopeKey<int>(0);

ScopeKey<int> countKey = ScopeKey.withDefault<int>(0);

Annotations

• @sealed

Constructors

ScopeKey([String? debugName])

Create a ScopeKey with a specific type.

ScopeKey.withDefault(T defaultValue, [String? debugName])

Create a ScopeKey that provides a default value if the key has not been added to the scope.

Properties

hasDefault → bool

Returns true if the key was created with a default value. A default has three states

no setter

hashCode → int

The hash code for this object.

no setter, inherited

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

Methods

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

testCast(dynamic v) → T

test if the keys value is of type T.

testFunctionCast(dynamic v) → T Function()

test if the keys function returns a value of type T.

toString() → String

A string representation of this object.

override

Operators

operator ==(Object other) → bool

The equality operator.

inherited