TidalCycles palindrome alternates a pattern between forward and backward playback every other cycle

palindrome p applies rev to pattern p every other cycle, causing the pattern to alternate between its normal forward order and its reversed order. palindrome $ sound "arpy:0 arpy:1 arpy:2 arpy:3" produces: forward one cycle, backward the next, forward again, etc. It is exactly equivalent to every 2 rev. The result over two cycles is the same as slow 2 $ sound "arpy:0 arpy:1 arpy:2 arpy:3 arpy:3 arpy:2 arpy:1 arpy:0". This is a compact way to add melodic variation to a repeating sequence without writing new material: the reversal creates a natural arch or palindromic phrase shape.

Examples

d1 $ palindrome $ sound "arpy:0 arpy:1 arpy:2 arpy:3"
-- same as:
d1 $ every 2 rev $ sound "arpy:0 arpy:1 arpy:2 arpy:3"

Assessment

What does palindrome $ s "bd sn hh cp" sound like over four cycles? Write the equivalent using every. Describe a musical context where palindrome structure is particularly effective.