Scratch 3.0 supports a few blocks that aren't available in the editor, but which work fine when copied between projects via the backpack or .sb3 files. This project contains blocks that you can copy, along with examples of how to get the same behavior without those blocks. Press 1, 2, 3, or 4 to run the examples.
"while" checks its condition at the beginning of each loop, which is subtly different from "repeatUntil", which checks its condition at the end of each loop. Beware of off-by-one errors and "while" loops that run zero times. "all at once" doesn't appear to do anything in the current version of Scratch. To get all-at-once behavior, use a custom block set to "run without screen refresh", or hold shift and click the green flag to enable turbo mode.
