Editing Fortran (section)

===Fortran-based languages===
Prior to FORTRAN 77, many [[preprocessor]]s were commonly used to provide a friendlier language, with the advantage that the preprocessed code could be compiled on any machine with a standard FORTRAN compiler.<ref>{{cite journal|url=https://dl.acm.org/doi/10.1145/987316.987320| title=On extending Fortran control structures to facilitate structured programming|publisher=acm.org|author=Meissner, Loren|journal=ACM SIGPLAN Notices|date=1975-09-01|volume=10|issue=9 | pages=19–30| doi=10.1145/987316.987320}}</ref> These preprocessors would typically support [[structured programming]], variable names longer than six characters, additional data types, [[conditional compilation]], and even [[Macro (computer science)|macro]] capabilities.  Popular preprocessors included [[EFL (programming language)|EFL]], [[FLECS]], [[iftran]], [[Mortran|MORTRAN]], [[SFtran]], [[S-Fortran]], [[Ratfor]], and [[Ratfiv]].  EFL, Ratfor and Ratfiv, for example, implemented [[C (programming language)|C]]-like languages, outputting preprocessed code in standard FORTRAN 66.  The [[PFORT]] preprocessor was often used to verify that code conformed to a portable subset of the language.  Despite advances in the Fortran language, preprocessors continue to be used for conditional compilation and macro substitution.

One of the earliest versions of FORTRAN, introduced in the '60s, was popularly used in colleges and universities.  Developed, supported, and distributed by the [[University of Waterloo]], [[WATFIV|WATFOR]] was based largely on FORTRAN IV.  A student using WATFOR could submit their batch FORTRAN job and, if there were no syntax errors, the program would move straight to execution.  This simplification allowed students to concentrate on their program's syntax and semantics, or execution logic flow, rather than dealing with submission [[Job Control Language]] (JCL), the compile/link-edit/execution successive process(es), or other complexities of the mainframe/minicomputer environment.  A down side to this simplified environment was that WATFOR was not a good choice for programmers needing the expanded abilities of their host processor(s), e.g., WATFOR typically had very limited access to I/O devices. WATFOR was succeeded by [[WATFIV]] and its later versions.

{{sxhl|2=fortran|1=program; s=0 i=1,n; s=s+1; stop i; s='s'  Stop}}  (line programming)

[[LRLTRAN]] was developed at the [[Lawrence Radiation Laboratory]] to provide support for vector arithmetic and dynamic storage, among other extensions to support systems programming.  The distribution included the [[Livermore Time Sharing System]] (LTSS) operating system.

The Fortran-95 Standard includes an optional ''Part 3'' which defines an optional [[conditional compilation]] capability.  This capability is often referred to as "CoCo".

Many Fortran compilers have integrated subsets of the [[C preprocessor]] into their systems.

[[SIMSCRIPT]] is an application specific Fortran preprocessor for modeling and simulating large discrete systems.

The [[F (programming language)|F programming language]] was designed to be a clean subset of Fortran 95 that attempted to remove the redundant, unstructured, and deprecated features of Fortran, such as the {{code|EQUIVALENCE}} statement.  F retains the array features added in Fortran 90, and removes control statements that were made obsolete by structured programming constructs added to both FORTRAN 77 and Fortran 90.  F is described by its creators as "a compiled, structured, array programming language especially well suited to education and scientific computing".<ref>{{cite web|url=http://www.fortran.com/F/index.html|title=F Programming Language Homepage|publisher=Fortran.com|access-date=November 19, 2014|archive-date=January 9, 2015|archive-url=https://web.archive.org/web/20150109130310/http://www.fortran.com/F/index.html|url-status=dead}}</ref> Essential Lahey Fortran 90 (ELF90) was a similar subset.

Lahey and Fujitsu teamed up to create Fortran for the Microsoft [[.NET Framework]].<ref>{{cite web | url=http://www.lahey.com/lf71/lfnet.htm | title=Fortran for .NET Language System | url-status=dead | archive-url=https://web.archive.org/web/20141018201259/http://www.lahey.com/lf71/lfnet.htm | archive-date=October 18, 2014}}</ref> Silverfrost FTN95 is also capable of creating .NET code.<ref>{{cite web | url=http://www.silverfrost.com/11/ftn95_overview.aspx | title=FTN95: Fortran 95 for Windows|publisher=Silverfrost.com|access-date=November 19, 2014}}</ref>