For anyone wanting to learn about parsers (specifically those used in an IDE), I found Dissecting a C# Application: Inside SharpDevelop has 3 chapters that deal with writing a (partial) parser for a C# IDE:

Chapter 12 - Writing the Parser

Chapter 13 - Code Completion and  Method Insight

Chapter 14 - Navigating code with the Class Scout and the Assembly Scout

Makes for an interesting read, plus you get the code ... all for free!