Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!sun-barr!apple!ames!vsi1!altos86!elxsi!beatnix!corbett
From: corbett@beatnix.UUCP (Bob Corbett)
Newsgroups: comp.lang.fortran
Subject: Fortran 8x:  recursive data types
Message-ID: <2775@elxsi.UUCP>
Date: 26 Jun 89 23:16:07 GMT
Sender: news@elxsi.UUCP
Reply-To: elxsi!uunet!corbett (Bob Corbett)
Distribution: usa
Organization: ELXSI, San Jose
Lines: 18


     There has been a proposal that pointers in Fortran 8x should be
replaced with recursive data types.  I know I oppose the idea, but I
am not sure why.  The proposal I saw did not spell out what the author
meant by recursive data types.  I have seen references to two forms of
recursive data types in the literature.  One form restricts the types
of data structures that can be constructed to trees.  If this form is
intended, I oppose it because I often use data structures, such as rings
and doubly-linked lists, that cannot be represented as trees.  The other
form of recursive data types allows fully general data structures to be
constructed.  This form is equivalent to using pointers, but the pointers
are implied rather than explicit.  I oppose this form of recursive data
types because when pointers are used, their use should be explicit.

                                                Yours very truly,
						Bob Corbett
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