Triggers

Introduction

Unlike in FTCLib and NextFTC, triggers in ducklib are any () -> Boolean-typed functions. No need to wrap them in a class, just use them as-is.

Binding actions and commands

Binding actions (() -> Unit-typed functions) to triggers involves using the TriggerScheduler's various binding functions.

onceOnTrue/onceOnFalse

These functions will run the action or schedule the command on the rising and falling edge of the supplier respectively.

whileOnTrue

This function accepts an action to run on the rising edge and on the falling edge. It's a convenience method for

trigger.onceOnTrue { /* do something */ }.onceOnFalse { /* do something else */ }

The command overload schedules the command on the rising edge and cancels it on the falling edge. If you want it to do the opposite, invert the trigger:

(!trigger).whileOnTrue(cmd)

Deferred variants

All the command-accepting onceOn* and whileOnTrue have deferred variants. These delay construction of the command until trigger time. This has some advantage over DeferredCommand. It's a more complete solution that doesn't require copying the requirements exactly, because the command construction happens before command initialization.