wait=false vs multitask

[MrGibbage]

Is there any advantage to using wait=false vs multitask() in pybricks? Our team has been using wait=false for a couple of years now, but I do see the multitask() a lot in here, so I wonder if we should be using that instead.

We currently use

# run the attachment motor while driving
drivebase.straight(distance=300, wait=false)
motor.run_angle(speed=100, rotation_angle=90)

Or should we be using multitask() code as suggested here: https://docs.pybricks.com/en/stable/tools/index.html?highlight=race#pybricks.tools.multitask

[dlech]

Is there any advantage to using wait=false vs multitask() in pybricks?

wait=False is probably easier to teach and learn for those who aren't experienced with async-style programming. For example, it is really easy to forget to always use await when needed when using multitasking.

On the other hand, there are some things that multitasking can do that just can't be done with wait=False. For example, run_until_stalled() doesn't have a wait parameter, but can be used in parallel with other actions when using multitasking.

So I would only change if A) you find a problem that it would solve that can't otherwise be solved or B) you are looking for a challenge to learn something new.

[laurensvalk]

This is good advice. To add some more context:

Deep down, it is still calling the same motor commands, so you don't lose/gain any performance. It is a matter of preference and what you want to achieve with your code.

Historically, we used to have only wait=False and added multitask later on. It is powerful in Python, but also works really well with blocks. Crucially, it doesn't just work with a single movement but any number of other blocks too.

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For example, this will drive the robot back and forth and log data in the mean time. You could do that with wait=False but it wouldn't look nearly as simple and clean as this:

And in case this piques your interest, here's what this program produces! (See more here.)

[MrGibbage]

Without a doubt, wait=False is very simple to explain. But something tells me that await multitask() would confuse them terribly. For now, wait=False works fine for us, so I think we will stick with that.