while

Type: Pattern Bool -> (Pattern a -> Pattern a) -> Pattern a -> Pattern a

while uses a binary pattern to conditionally apply a function to a source pattern. The function is applied when a "true" value is active, and the pattern remains unchanged when a "false" value is active.

For example, the following pattern changes the speed in the last quarter of the pattern:

d1 $ while "f f f t" (# speed 2) $ s "bd*8"

This code will reverse the pattern, but only in the first half of the pattern:

d1 $ while "t f" rev $ s "drum*8" # n "0 .. 7"

You can use Euclidean patterns, or more complex binary patterns, to achieve interesting results:

d1 $ while "t(<3 5>,8,<0 1 5>)" rev $ s "drum*8" # n "0 .. 7"