pxt-calliope/docs/blocks/loops/while.md
2016-06-14 17:20:45 -04:00

924 B

While

@parent blocks/language

Repeat code while a Boolean condition is true.

while(true) {
}

The while loop has a condition that evaluates to a Boolean value. After the do keyword, add the code that you want to run while the condition is true. The while loop concludes with end while.

The condition is tested before any code runs. Which means that if the condition is false, the code inside the loop doesn't execute.

Example: diagonal line

The following example uses a while loop to make a diagonal line on the LED screen (points 0, 0, 1, 1, 2, 2, 3, 3, 4, 4).

let index = 4;
while(index >= 0) {
    led.plot(index, index);
    index--;
}

See also

on button pressed, for, if, forever