Actors is a key concept in Acton. Each actor is a small sequential process with its own private state. Actors communicate with each other through messages, in practice by calling methods on other actors or reading their attributes.


# An actor definition
actor Act(name):

    # Top level code in an actor runs when initializing an actor instance, like
    # __init__() in Python.
    print("Starting up actor " + name)
    def hello():
        # We can directly access actor arguments, like `name`
        print("Hello world from " + name)

actor main(env):
    # Create an actor instance a of Act
    a = Act("FOO")
    # Call the actor method hello
    await async a.hello()


Compile and run:

actonc actors.act


No dependencies found, building project
Building project in /tmp/tmp_nwgl0ik/example
  Compiling example.act for release
   Finished compilation in   0.015 s
  Final compilation step
   Finished final compilation step in   0.437 s
Starting up actor FOO
Hello world from FOO