The new features of Fortran 2000
John K. Reid · ACM SIGPLAN Fortran Forum · 2002
The aim of this paper is to summarize the new features in the draft Fortran 2000 standard (J3 2002). We take as our starting point Fortran 95 plus the two official extensions (Cohen 2001, Reid 2001) that have been published as Type 2 Technical Reports. These provide features for1. Allocatable dummy arguments and type components, and2. Support for the five exceptions of the IEEE Floating Point Standard (IEEE 1989) and for other features of this Standard.There is a firm commitment to include the features of these TRs in Fortran 2000, apart from changes that follow from errors and omissions found during implementation. Therefore, these features are not open to comment and are not described here. For an informal description, see chapters 12 and 13 of Metcalf and Reid (1999).Fortran 2000 is a major extension of Fortran 95. This contrasts with Fortran 95, which was a minor extension of Fortran 90. The major changes concei'n the two TR items, object orientation, and interfacing with C. Allocatable arrays are very important for optimization - after all, good execution speed is Fortran's forte. Exception handling is needed to write robust code. Object orientation provides an effective way to separate programming into independent tasks and to build upon existing codes; we describe these features in Section 1. Interfacing with C is needed for access to the all the hardware features and to allow C programmers to call efficient Fortran codes; we describe these features in Section 4. There are also many less major enhancements, described in Sections 2 and 3.