Split string based on regex

Question

What is the best way to split a string like \"HELLO there HOW are YOU\" by upper case words (in Python)?

So I\'d end up with an array like such:

Answer 1

You could use a lookahead:

re.split(r'[ ](?=[A-Z]+\b)', input)

This will split at every space that is followed by a string of upper-case letters which end in a word-boundary.

Note that the square brackets are only for readability and could as well be omitted.

If it is enough that the first letter of a word is upper case (so if you would want to split in front of Hello as well) it gets even easier:

re.split(r'[ ](?=[A-Z])', input)

Now this splits at every space followed by any upper-case letter.

Answer 2

Your question contains the string literal "\b[A-Z]{2,}\b", but that \b will mean backspace, because there is no r-modifier.

Try: r"\b[A-Z]{2,}\b".

Answer 3

I suggest

l = re.compile("(?<!^)\s+(?=[A-Z])(?!.\s)").split(s)

Check this demo.