Registers Callback to be invoked each time Signal is called.
Call Cancel on the returned cancelable to unregister Callback.
Verse using statement |
using { /Verse.org/Verse } |
Subscribe<native><override>(Callback:(), , , :void)<transacts><predicts><dictates>:cancelable
Parameters
Subscribe takes the following parameters:
| Name | Type | Description |
|---|---|---|
Callback |
(), , , :void |
Attributes, Specifiers, and Effects
Specifiers
The following specifiers determine how you can interact with Subscribe in your programs. For the complete list of specifiers, see the Specifiers Page.
| Specifier | Meaning |
|---|---|
native |
Indicates that the definition details of the element are implemented in C++. Verse definitions with the native specifier auto-generate C++ definitions that a developer can then fill out its implementation. You can use this specifier on classes, interfaces, enums, methods, and data. |
override |
Indicates that this child class provides a different method implementation than the parent class. |
Effects
The following effects determine how Subscribe behaves in your programs. For the complete list of effects, see the Effect Specifers section of the Specifiers Page.
| Effect | Meaning |
|---|---|
transacts |
This effect indicates that any actions performed by the function can be rolled back. The transacts effect is required any time a mutable variable (var) is written. You’ll be notified when you compile your code if the transacts effect was added to a function that can’t be rolled back. Note that this check is not done for functions with the native specifier. |
predicts |
|
dictates |