• CLI
• meta-programming
• query

This thesis proposes a query language for code selection. It is designed to work on virtual machine based languages and is intended to be used to find regions of code that match a pattern defined by a query. Queries are defined by methods following the query-by-example approach and are performed using a query operator. The query operator we describe is perceived at high level language but performs queries at virtual machine intermediate language. The matching process and operators described are similar to the ones used in regular expression pattern matching but with some differences, for example, these patterns have code instructions as symbols.
We have developed a prototype (Code Query) that implements the query operator and provides an API to perform queries. Code Query is implemented in C# on CLI platform.
Our approach allows cross-language queries with the only constraint that such languages must target the same virtual machine. Our work can be used to develop a framework for aspect oriented programming that does not require modification or extension to the virtual machine compiler and that can match not only join points but also any arbitrary portion of code.