Interface Type

Declaration

Interfaces in Aura can be declared using the interface keyword like so:

interface IGreeter { ... }

Interfaces can be declared as either public or private using the pub keyword preceding the interface keyword. The previous example defines a private interface - to declare a public one, you could update the interface declaration like so:

pub interface IGreeter { ... }

The body of an interface contains any methods that must be implemented by classes that implement the interface. These methods in the interface's body should not contain function bodies, and are implicitly understood to be public, meaning they do not need the pub visibility modifier. An example interface might look like this:

pub interface IGreeter {
    say_hi(name: string) -> string
}

Implementation

Classes must explicitly implement an interface, which is done like so:

class Greeter : IGreeter { ... }

In this case, the Greeter class must implement the say_hi method defined in the IGreeter interface, and its implementation of the say_hi method must be marked with the pub visibility modifier. Failure to do so will result in an error during the compilation process.

Classes can implement any number of interfaces. When implementing more than one interface, the interfaces should be separated by a comma, like so:

class Greeter : IGreeter, ISmallTalker { ... }

Last modified: 03 April 2024