⌂ Time signature with alternate in parentheses

In polymetric music, a composer may indicate beat structure by following one time signature with another in parenthesis, for example: 3/4 (6/8) indicating a 6/8 beat in a 3/4 measure, or 6/4 (6/8) indicating a 6/8 beat in a 6/4 measure. This snippet is derived from the parenthesize-time snippet, adding an unparenthesized fraction in front of the parenthesized one.