JSON parser
JSON is used day in and day out everyday. A majority of the APIs today converse in JSON. By building a JSON parser from scratch, we'll learn some fundamentals on how parsers work. These fundamentals are also applicable to how languages are build from scratch.
Let's break the parsing into two independent pieces, the first part will make sure that the structure is correct. As in all the individual pieces make sense and get rid of useless cruft. In the second step we'll check if the pieces make sense together.
Let's start breaking down the raw string into pieces (also called tokens).