Structure: [future = ]()[ : ] f = doSomething(1, 2) // Async print f // Block f = doSomething(1, 2) // Async sync f // Block (or `wait f` or whatever) doSomething(1, 2) : {v| print v} // Async, prints result when ready doSomething(1, 2) : some-channel // Async, result gets sent to `some-channel`