Thanks David that would help me to solve the problem – However I have just had a Eureka moment …
So my target was to define “find any white space except a forced line break” as part of a wider find / change:
I want to find all instances of a pipe “|” and make sure that it is surrounded by a space on both sides – ” | ”
I do not want to select a forced line break if there is one
So I did this = (?<=.)\s*?\|\s*?(?=\n*\w) and replace with ” | “