Path: utzoo!utgpu!water!watmath!clyde!rutgers!ukma!gatech!udel!rochester!bbn!uwmcsd1!ig!agate!ucbvax!FSU.BITNET!adk
From: adk@FSU.BITNET (Tony Kennedy)
Newsgroups: comp.os.vms
Subject: Zero length strings in Fortran.
Message-ID: <[gw.scri.fsu.edu].B08F73A0.0090E265.ADK>
Date: 9 Feb 88 22:31:00 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 24


   From: ZSYJKAA@WYOCDC1.BITNET (Jim Kirkpatrick 307 766-5303)
   Subject: FORT vs. zero-length strings

   If anybody has the ANSI standard handy, could you look up the formal
   definition of a character string and let us (or me) know if zero-length
   strings are OK? I'd hate to flame DEC if ANSI deserves it instead.
----------------------------------------
(A) Zero length strings are not valid in ANSI FORTRAN 77.
(B) Zero length strings are valid in the current Fortran 8x draft.
(C) Your discussion of padding strings etc. is not quite right. The problem
    in the program fragment

        CHARACTER*(8) STRING
        ...
        STRING = ''

    is that the character constant ('') is invalid because it has length
    zero. If it were valid, it would then be padded to a string of length
    eight containing only spaces. In this case using a length one string
    containing a space (' ') would work just fine.

Please note that I am not saying the FORTRAN 77 behaviour is a good thing,
I am just saying that it is what it is!