Pattern matching and regular expressions

Pattern matching, which plays a key role in Go, is a technique for searching a string for a set of characters based on a specific search pattern that is based on regular expressions. If pattern matching is successful, it allows you to extract the desired data from the string or replace or delete it. Grammar is a set of production rules for strings in a formal language. The production rules describe how to create strings from the alphabet of the language that are valid according to the syntax of the language. Grammar does not describe the meaning of a string or what can be done with it in whatever context, only its form. What is important is to realize that grammar is at the heart of regular expressions because without it, you cannot define or use a regular expression.

Regular expressions and pattern matching are not a panacea, so you should...