Editing Fortran (section)

===Fortran 95===
{{Redirect|F95|the Düsseldorf-based football club nicknamed "F95"|Fortuna Düsseldorf}}
{{Main|Fortran 95 language features}}
''Fortran 95'', published officially as ISO/IEC 1539-1:1997, was a minor revision, mostly to resolve some outstanding issues from the Fortran 90 standard.  Nevertheless, Fortran 95 also added a number of extensions, notably from the [[High Performance Fortran]] specification:

* {{code|FORALL}} and nested {{code|WHERE}} constructs to aid vectorization
* User-defined [[pure function|{{code|PURE}} and {{code|ELEMENTAL}} procedures]]
* Default initialization of derived type components, including pointer initialization
* Expanded the ability to use initialization expressions for data objects
* Initialization of pointers to {{code|NULL()}}
* Clearly defined that {{code|ALLOCATABLE}} arrays are automatically deallocated when they go out of scope.

A number of intrinsic functions were extended (for example a {{code|dim}} argument was added to the {{code|maxloc}} intrinsic).

Several features noted in Fortran 90 to be "obsolescent" were removed from Fortran 95:

* {{code|DO}} statements using {{code|REAL}} and {{code|DOUBLE PRECISION}} index variables
* Branching to an {{code|END IF}} statement from outside its block
* {{code|PAUSE}} statement
* {{code|ASSIGN}} and assigned {{code|GO TO}} statement, and assigned format specifiers
* {{code|H}} Hollerith edit descriptor.

An important supplement to Fortran 95 was the [[International Organization for Standardization|ISO technical report]] ''TR-15581: Enhanced Data Type Facilities'', informally known as the ''Allocatable TR.''  This specification defined enhanced use of {{code|ALLOCATABLE}} arrays, prior to the availability of fully Fortran 2003-compliant Fortran compilers.  Such uses include {{code|ALLOCATABLE}} arrays as derived type components, in procedure dummy argument lists, and as function return values.  ({{code|ALLOCATABLE}} arrays are preferable to {{code|POINTER}}-based arrays because {{code|ALLOCATABLE}} arrays are guaranteed by Fortran 95 to be deallocated automatically when they go out of scope, eliminating the possibility of [[memory leak]]age.  In addition, elements of allocatable arrays are contiguous, and [[aliasing (computing)|aliasing]] is not an issue for optimization of array references, allowing compilers to generate faster code than in the case of pointers.<ref>{{cite web|title=Fortran 95 Reference|url=https://gcc.gnu.org/onlinedocs/gcc-4.1.0/gfortran/|publisher=Gnu.Org|access-date=May 10, 2014}}</ref>)

Another important supplement to Fortran 95 was the [[International Organization for Standardization|ISO]] technical report ''TR-15580: Floating-point exception handling'', informally known as the ''IEEE TR.''  This specification defined support for [[IEEE 754-2008|IEEE floating-point arithmetic]] and [[floating-point arithmetic|floating-point]] [[exception handling]].

====Conditional compilation and varying length strings====
In addition to the mandatory "Base language" (defined in ISO/IEC 1539-1 : 1997), the Fortran 95 language also included two optional modules:
* Varying length character strings (ISO/IEC 1539-2 : 2000)
* Conditional compilation (ISO/IEC 1539-3 : 1998)
which, together, compose the multi-part International Standard (ISO/IEC 1539).

According to the standards developers, "the optional parts describe self-contained features which have been requested by a substantial body of users and/or implementors, but which are not deemed to be of sufficient generality for them to be required in all standard-conforming Fortran compilers." Nevertheless, if a standard-conforming Fortran does provide such options, then they "must be provided in accordance with the description of those facilities in the appropriate Part of the Standard".