How to ignore whitespace in a regular expression subject string?

While the accepted answer is technically correct, a more practical approach, if possible, is to just strip whitespace out of both the regular expression and the search string.

If you want to search for "my cats", instead of:

myString.match(/m\s*y\s*c\s*a\*st\s*s\s*/g)

Just do:

myString.replace(/\s*/g,"").match(/mycats/g)

Warning: You can't automate this on the regular expression by just replacing all spaces with empty strings because they may occur in a negation or otherwise make your regular expression invalid.

You can stick optional whitespace characters \s* in between every other character in your regex. Although granted, it will get a bit lengthy.

/cats/ -> /c\s*a\s*t\s*s/