There is any notation for a language that is empty infinite? Assume that $L$ is a language, is there any established notation that means that $L$ is infinite or empty?
The usual way to describe these properties is by indicating the size of $L$, denoted by $|L|$.


Empty language, the size is zero, $|L|=0$
Finite language, $|L|=c$ or in general, the size in non-infinite, $|L|&lt; \infty$    
Infinite language, $|L|=\infty$.