Take class

Creates an Effect description that instructs the middleware to wait for a specified action on the Store or if provided on the channel. The Generator is suspended until an action that matches pattern is dispatched.

The result of yield Take(pattern : pattern) is an action object being dispatched.

pattern is interpreted using the following rules:

  • If Take is called without pattern argument or '*' all dispatched actions are matched (e.g. Take() will match all actions).

  • If it is a function, the action is matched if pattern(action) is true.

  • If it is a Type, the action is matched through its type. The logic is action.runtimeType === pattern (e.g. Take(pattern: IncrementAsync). Type matcher may be enough to solve most scenarios. It is also type safe and easy to use.

  • If it is a String, the action is matched if its type name as string equals the String. The logic is action.runtimeType.toString() === pattern (e.g. Take(pattern: 'IncrementAsync').

  • If it is an array, each item in the array is accepted as pattern and all must match, so the mixed array of types, strings and function predicates is supported. The most common use case is an array of types though, so that action type is matched against all items in the array (e.g. Take(pattern: [Increment, Decrement]) and that would match either actions of type Increment or Decrement).

The middleware provides a special action End. If you dispatch the End action, then all Sagas blocked on a Take Effect will be terminated regardless of the specified pattern. If the terminated Saga has still some forked tasks which are still running, it will wait for all the child tasks to terminate before terminating the Task.

Inheritance
Implementers

Constructors

Take({dynamic pattern, Channel? channel, bool maybe = false, Result? result})
Creates an instance of a Take effect.

Properties

channel → Channel?
Instructs the middleware to wait for a specified message from the provided Channel. If the channel is already closed, then the Generator will immediately terminate following the same process described for Take.
final
hashCode → int
The hash code for this object.
no setterinherited
maybe → bool
If true Take does not automatically terminate the Saga on an End action. Instead all Sagas blocked on a take Effect will get the End object. Check TakeMaybe also.
final
pattern → dynamic
Actions only matching pattern is taken.
final
result ↔ Result?
Result after effect is resolved.
getter/setter pairinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

getDefinition() → Map<String, dynamic>
Returns all properties of effect as a dictionary object
override
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toString() → String
A string representation of this object.
inherited

Operators

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