I’m struggling with a conditional transform. seems simple but I can’t work it out. How do I transform a map value only if it is present?

(transform [:b vector?] set {:a 1})

will return {:a 1, :b nil}

but I only want the “:b” transformed if “:b” is present

@steveb8n (s/must :b)

https://github.com/nathanmarz/specter/wiki/List-of-Navigators#must

thanks @schmee I knew there had to be a simple answer