I think there should be a block, like “When I Recieve” but a boolean. It would work like this (replace mouse down? with the boolean)
when flag clicked
forever
wait until mouse down?
stamp
end
The block would go in the control tab.
chocolatepenguin

This has been suggested multiple times, and the fact is, it's not even really possible as a broadcast is only a millisecond or so long.

ImagineIt wrote:

a broadcast is only a millisecond or so long.

it's instant, when a message is broadcasted, it checks for “when I receive …”s.

there is a way to do this! however, its not really good working. the trick: make a variable. let's say you broadcasted “start”. then, make the variable called: “start received?”. in the stage, put the scripts ( the “//” means a comment):
when gf clicked
set (start received?) to (false) // You write “false”, not put a boolean that reports “false”

Then, put this script:
when I receive (start)
set (start received?) to (true) // You write “true”, not put a boolean that reports “true”
wait (0.5) secs
set (start received?) to (false)

Let's say that a sprite rotates until it receives “start”.
Put this script in the sprite:
when gf clicked
repeat until < ((start received?) = (true)) >
turn clockwise 15 degrees
end

YOU GOT IT!!

A Boolean broadcast is a rejected suggestion. However, Wait until broadcast and Repeat until broadcast are not rejected and you can find the thread discussing them here.

Yep, this is rejected. Also seeing how this topic is now 6 years old, I should probably close it.

Za-Chary wrote:

1.1 “Broadcast received” boolean block
Some users want a block that looks like the block below, referencing broadcasts. But, there is a lot of ambiguity on how this would work. Would it return true if the broadcast was fired since the project was created, since the green flag was clicked, or since something else was broadcasted? The workaround is simple: use variables that change when a broadcast is received, then use the “equals” block.

However, the blocks “repeat until broadcast received” and “wait until broadcast received” are NOT rejected; you can discuss them on this post.

<[message v] received? :: events>