Seastar Example

Pythia includes syntax for calling and chaining lambda functions. The syntax below and then(): chains a new lambda function to the previous one. The functions are defined under with stack: are set to use stack memory mode (CPU Cache). note: the default memory mode is c++11 smart pointers (reference counted garbage collection).

with stack:
    def delay(seconds) -> future<>:
        print 'sleeping', seconds
        sleep(seconds)
        return future

    def f() -> future<>:
        delay(1) and then():
            print 'sleep1'
            and then():
                print 'sleep1.1'
                delay(1) and then():
                    print 'nested 1.1:1'
                    and then():
                        print 'nested 1.1:2'

            and then():
                print 'sleep1.2'
                and then():
                    print 'sleep1.2.1'

        delay(2) and then():
            print 'sleep2'

        return delay(3) and then():
            print 'all done'