⌂ Graphic measure grouping indications for conductors

In 20th century music, time signatures tend to change frequently and to be more complex. Therefore, printing graphic indications (such as brackets and triangles) above the top staff has become quite useful, if not essential, to conductors or even players. LilyPond is able to do that easily with its integrated Measure_grouping_engraver.

Beware: you can no longer use the \time command; use instead the #(set-time-signature x x '(x x) function, which is quite more powerful, especially for compound time signatures such as 5/8.