[buckbova]

If you are looking for somewhere to craft regexes, someone recently posted a link to a neat looking project, regex101 http://regex101.com/ .

This link looks to be driving traffic to this myezapp.

[yeukhon]

The problem with regex101 is the explaination is not so easy to read. It contains some extra helpful information like a list of "whitespace characters". Try this: \s+HelloWorld\s+

The OP's tool seems better at explaining, though the "one or more times" could be said in repeat much earlier.