It has been said before that if you have a problem and your solution is to use regular expressions, you now have two problems. Regular expression is a term used to represent the language to identify patterns found in text. The language itself is terse (a single character in this language can have a complex meaning). In the open source community, the most identifiable example of regular expressions in use is with the command-line tool,
grep. The name is derived from an older text editor called
ed, which had a command called
grep, we can search for a pattern of text in a file and filter out anything that does not contain this pattern, for example, let's assume that we have a text file that represents ...