The string written in quotes matches literally. Also used to remove the special meaning of characters as defined in this table. Indicates how many times a pattern can be present.Įxample: A implies one or three occurrences of A may be present. Matches the end of the line as the last character of the pattern. – Used to denote a range.Įxample: implies all characters from A to Z. Used as for negation in Character class.Ī character class. Matches the beginning of a line as the first character.Įxample: ^verb means input starts with a verb wordĢ. Match with zero or one occurrence of the preceding pattern or expression.Įxample: -?* : starts with an – signġ. Matches with one or more occurrences of the preceding pattern. Match with zero or more occurrences of the preceding pattern or expression. Characters that form the regular expressions: Regular Expression Definition of Regular Expressions:Ī Regular Expression is a pattern description using a “meta” language, a language that you use to describe particular patterns of interest. In this article, we will discuss the concept of Regular Expressions LEX and YACC and different LEX actions used while writing LEX programs. Join for Regular Updates Regular Expressions in LEX and YACC
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |