Dating for dummies pdf
Each node in the AST is an instance of a class, with qualifying attributes (e.g."21:") and possibly children - for example, the One Or More class must have something to work on, which is represented by a child instance.Both of these help with the lexical and parsing phase, and use a specification of the syntax/grammar to do their work.In computing terms, many of the ideas about compilers are not old - they're positively ancient.The rules for writing correct programs are often called the concrete syntax; and it has its own rules of composition just as the abstract syntax does.As you have probably guessed from the section title, the processing of DSL's proceeds exactly as for general purpose languages.It is a good place to start to understand today's code generation landscape.
[a-z] A range, given in the  brackets, in this case it is from a-z. Using the preceding regular expression, match one or more of them. Most modern editors allow you to search files for a regular expression and they're very useful in certain situations.and it has all sorts of new terms and ideas swirling around it.