IRPF90 is a Fortran code generator which helps the development of large Fortran codes. In Fortran programs, the programmer has to focus on the order of the instructions: before using a variable, the programmer has to be sure that it has already been computed in all possible situations. For large codes, it is common source of error.
Using IRPF90 most of the order of instructions is handled by the pre-processor, and an automatic mechanism guarantees that every entity is built before being used. This mechanism, relies on the {needs/needed by} relations between the entities, which are built automatically. The consequence is that the programmer doesn’t need to know the production tree of each entity.
Codes written with IRPF90 execute usually faster than Fortran programs, are faster to write and easier to maintain than standard Fortran programs.