Path: utzoo!attcan!uunet!cs.utexas.edu!tut.cis.ohio-state.edu!purdue!haven!umbc3!mbph!hybl
From: hybl@mbph.UUCP (Albert Hybl  Dept of Biophysics  SM)
Newsgroups: comp.lang.fortran
Subject: Re: Character aliases are Satanic extensions
Summary: X3J3 scores a perfect 10.00
Message-ID: <594@mbph.UUCP>
Date: 12 May 89 17:13:59 GMT
References: <592@mbph.UUCP> <177@csun1.UUCP>
Organization: University of Maryland, School of Medicine, Baltimore, MD 21201
Lines: 78


From article <177@csun1.UUCP> by weyrich@csun1.UUCP (Orville Weyrich):
> What you describe was correct FORTRAN-66, ...  FORTRAN is a permissive
> standard that stresses what is required to be supported. It does not
> prohibit the support of extensions or anachronisms as long as they do
> not directly conflict with required features.

The ANSI X3.9-1978 FORTRAN language standard is explicit in
the definition of integer, real, double precision and character
types.  Nowhere in the X3.9 standard is there any hint that
integer, real or double precision variables can serve as character
aliases.  Indeed, to do so would directly contravene the type
definitions.  The standard has been in place for more than ten year.
The character type statement was intended to supplant the multitude
of aliases used in the then existing FORTRAN compilers.  Do you think
that the following program will will produce the answer:  '120_miles' ?
It compiles without diagnostics on a VAX! :-(

      double precision distance, time, speed
      time='2_hours'
      speed='60_mph'
      distance=time*speed
      print *, distance
      end

The programs I am porting bear dates 1984-1986 not 1974.  Perusal
of the colorful VAX VMS FORTRAN Language Reference Manual divulges
a description _with examples_ on how to use the Satanic character
aliases.  The description is not relegated to an appendix nor does
it discourage the continued use of such coding.  The implementors
of the VAX VMS FORTRAN should be excoriated for promoting the
perpetuation of such anachronistic coding practices.

The _NEW WORLD DICTIONARY_ defines "standard" as (1) any figure
or object, esp, a flag or banner, used as an emblem or symbol of
a leader, people, military unit, [fortran language implementor],
etc ... (2) something established for use as a rule or basis of
comparison in measuring or judging capacity, quantity, content,
extent, value, quality, [portability, readability, maintainability] ...

Do you think that the second definition applies to the X3.9
FORTRAN language standard?  Then read the following snippet.
It was carefully crafted by the acolytes of Mammon.  Although
it provides me with the opportunity to rate different FORTRAN
implementations in a demolition derby, it is the cause of the
poor portability of FORTRAN programs.  The X3J3 committee scores
a perfect 10.00 for allowing implementors to add his/her flag
to their products.  Have you tried to install a VWvan wheel or glow
plug on an International Harvester Travelall?

: 	1.3.2. _Exclusions_.  This standard does not specify:
: 	    [...]
: 	  (4) The results when the rules of this standard fail
: 	      to establish an interpretation.
: and:
: 	1.4. _Conformance_
: 	  [...]
: 	A processor conforms to this standard if it executes
: 	standard-conforming programs in a manner that fulfills the
: 	interpretations prescribed herein.  A standard-conforming
: 	processor may allow additional forms and relationships
: 	provided that such additions do not conflict with the
: 	standard forms and relationships.  [...]

>I agree that a filter program that removes anachronisms would be
>nice, ...  But it is not an easy task. ...

Would it be challenging as a computer science project?  I think
I would like to see several user selectable exorcisms.  They should
be written in a portable language--like C, awk, SNOBOL or ICON :-)/2

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Albert Hybl, PhD.              Office UUCP: uunet!mimsy!mbph!hybl
Department of Biophysics       Home   UUCP: uunet!mimsy!mbph!hybl!ah
University of Maryland                CoSy: ahybl
School of Medicine
Baltimore, MD  21201                 Phone: (301) 328-7940 (Office)
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