ISO/IEC JTC1/SC22/WG5 N1459
From Dan Nagle
To WG5
Subject Fortran 2000 Summary

With almost no exceptions (1.5.1), Fortran 2000 is a superset of
Fortran 95.  Fortran 2000 contains several extensions to Fortran 95,
these include the following.

o  Derived type enhancements, specifically parameterised derived types
   (allowing the kind, length or dimension of a derived type's
   components to be chosen when the derived type is used), mixed
   component accessibility (where different components have different
   accessibility), public entities of private type, improved
   constructors and finalizers (destructors).

o  Object oriented programming support, specifically extensible types
   (providing inheritance), inheritance (where one type extends the
   definition of another type), polymorphism (where the type of a
   variable may vary at runtime), dynamic type allocation 
   and type-bound procedures.

o  The ASSOCIATE construct (which allows a complex expression or object
   to be denoted by a simple symbol) & SELECT TYPE construct (which
   allows a choice of execution flow depending upon which type a
   polymorphic object currently has).

o  Data manipulation enhancements, specifically allocatable components,
   deferred type parameters, VOLATILE attribute (where the processor
   is warned to always use the value of a datum found in memory,
   allowing the value in memory to change by a means beyond the
   program itself), explicit type specification in array constructors,
   INTENT specification of pointer arguments, specified lower bounds 
   of pointer assignment and pointer rank remapping, extended
   initialisation expressions, MAX & MIN intrinsics for character
   type and enhanced complex constants.

o  Input/output enhancements, specifically asynchronous transfer
   operations (where a program can continue to process data while an
   input/output transfer occurs), stream access (which facilitates
   access to a file without reference to any record structure), user
   specified transfer operations for derived types, user specified 
   control of rounding during format conversions, named scratch
   files, named constants for preconnected units, and access to
   input/output error messages.

o  Pointers to procedures & abstract interfaces (which give names
   for the specified interfaces).

o  Scoping enhancements, specifically the ability to rename defined
   operators (which supports greater data abstraction), and control
   of host association into interface bodies.

o  Support for IEC 60559 (formerly IEEE 754) exceptions & arithmetic
   (to the extent a processor's arithmetic supports the IEC standard).

o  Interoperability with the C programming language (allowing
   portable access to many libraries and the low-level facilities
   provided by C and allowing the portable use of Fortran libraries
   by programs written in C).

o  Support for international usage (via support for Unicode
   ISO 10646) & point v. comma in numeric formatted i/o.

o  More complete integration with the host operating system,
   specifically access to command line arguments (where supported)
   and environment variables (where supported), and access to the
   processor's error messages (which allows the program to better
   process exceptional conditions).