![]() (?P=name) (Python-style named backreference) (?Pregex) (Python-style named capturing group \k'name' (.NET-style named backreference) (?'name'regex) (.NET-style named capturing group) ![]() (?regex) (.NET-style named capturing group) (?ismxn:group) (mode modifiers local to group) ? after any of the above quantifiers to make it "lazy"īackreferences non-existent groups are an errorīackreferences to failed groups also fail \Y (NOT at the beginning or end of a word) \B (NOT at the beginning or end of a word) \Q.\E escapes a string of character class metacharacters \Q.\E escapes a string of metacharactersīackslash escapes one character class metacharacter The special character * after the closing square bracket specifies to match zero or more occurrences of the character set. The regular expression * matches any sequence of letters that starts with an uppercase letter and is followed by zero or more lowercase letters. ![]() The regular expression matches "BIG", "BAG", "BIN", and "BAN". This regular expression matches "B", followed by an "I" or "A", followed by a "G" or "N". If you specified the regular expression as "B", the concatenation of character sets creates a regular expression that matches the corresponding concatenation of characters in the search string. The regular expression " BG " matches the strings "BIG", "BAG", and "BUG", but does not match the string "BOG". For example matches any single character that is not a capital letter. ![]() In a character set a ^ character negates the following characters. In the character set, a hyphen indicates a range of characters, for example will match any one capital letter. For example, the regular expression " " specifies to match any single uppercase or lowercase letter. The pattern within the brackets of a regular expression defines a character set that is used to match a single character. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |