Conditionally apply a Nunjucks filter

I have a Nunjucks filter that removes everything in a string after and including the first colon. I use it for removing the subtitle from books in my currently-reading list (Book Title: Obnoxiously Long Subtitle, As Is Common These Days → Book Title). In that macro/include, I pass in a parameter to determine whether I want the long or short version of the title. You can conditionally apply a Nunjucks filter like this:

{{ book.title | removeSubtitle if noSubtitle else book.title }}

This will output the filtered title if the noSubtitle variable is set; otherwise, the full title is output.