I wonder if there is anyone who would find more clarity in the regex than the English.

Yes, the regex is more clear, in the same sense that a picture is worth a thousand words.

@BassClefBuddha what do you mean seizure?

I dont se a problem with either.
The regex is quite straight forward, first char has to be a letter or an underscore or any ascii char number 127-255
From second also numbers are valid.

Start using look behind and look ahead and it starts to be interesting ;)

On the other hand, I have hand coded a few lexer/parsers so the concept is very familiar.

Why why why would you put a period after a regex?

@Ashkin I agree. Even if a sentence should end in some punctuation, I would prefer to have some clear separation since a dot is a valid part of a regex and anyone copying risk getting a regex that eats one char to much ;)