Structured programming is often regarded as "goto-less programming". But as Bertrand Meyer notes, "As the first book on the topic ["Structured Programming" by Dijkstra, Dahl, and Hoare] shows, structured programming is about much more than control structures and the goto. Its principal message is that programming should be considered a scientific discipline based on mathematical rigor." As a programming paradigm, structured programming – especially in the 1970s and 1980s – significantly influenced the birth of many modern programming languages such as Pascal, C, Modula-2, and Ada. The Fortran 77 version which incorporates the concepts of structured programming, was released in 1978. The C++ language was a considerably extended and enhanced version of the popular structured programming language C (see also: list of C-based programming languages). Since C++ was developed from a more traditional structured language, it is a 'hybrid language', rather than a pure object-oriented programming language.