A declarative language FlexT for analysis and documenting of binary data formats

The language FlexT (Flexible Types) is intended for specification of binary data formats. The language is declarative and designed to be well understood for human readers. Its main elements are the data type declarations, which look very much like the usual type declarations of the imperative programming languages, but are more flexible. In the article we first give a review of the capabilities of the modern projects oriented to specification of binary file formats. Then we consider the main features of the FlexT language and, in particular, the features that help to describe the formats of encoding of machine instructions. Finally we briefly describe the software developed, which is based upon the FlexT interpreter and some new capabilities of information search, which makes possible the use of the specifications.