Menu
I'm struggling with the following regexp
[A-z0-9]+ If tested against this string:
||a919238[.--a]asd| it returns a919238[, including the square bracket.. I tried to input my test case on regex101 to understand what's wrong, but the site regex explanation is not helping, probably I'm not able to see my mistake.
Why is the square bracket included in the result?
464
You can omit the first backslash. [[\]] will match either bracket. In some regex dialects (e.g. grep) you can omit the backslash before the ] if you place it immediately after the [ (because an empty character class would never be useful): [][] .
(?= regex_here) is a positive lookahead. It is a zero-width assertion, meaning that it matches a location that is followed by the regex contained within (?=
Use Parentheses for Grouping and Capturing. By placing part of a regular expression inside round brackets or parentheses, you can group that part of the regular expression together. This allows you to apply a quantifier to the entire group or to restrict alternation to part of the regex.
A regular expression (shortened as regex or regexp; sometimes referred to as rational expression) is a sequence of characters that specifies a search pattern in text. Usually such patterns are used by string-searching algorithms for "find" or "find and replace" operations on strings, or for input validation.
Because
[A-z0-9]+ ↑ ↑ is from A to z, see the ASCII table, ] appears between the two characters:
149
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
