If you want to design your own language, you might want to start with IParse Studio, an interactive online parser that parses input according a grammer at every keystroke returning a parse tree, if the input can be parsed according the grammar.

Once you have the grammar, you can use it with IParse developed in C++, which produces an abstract parse tree.

IParse has a build-in scanner for C like terminals, which are now used in many languages. You can implement your own scanner. IParse also has an unparser, which allows you to generate pretty printed output with just some annotations in the grammar.