Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
I have this ruby expression as below
(a|bc)(d?|e)*
when i use rubular to test out possible strings that fit this expression, I have some strings that I dont understand why they dont fit
the strings are “ade”, it matches “ad” but does not match the “e”. Anyone can help?
The second part of the regular expression you entered (d?|e)* is the problem. Putting the ? on the d says, match d 0 or 1 times. When you run through the string ade, the regex matches a, then d, then d 0 times… If you instead changed it to (a|bc)(d|e)*, it would match ade, and seem to have the semantics that you’re looking for.