Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!gatech!psuvax1!psuvm.bitnet!psuvmxa!cunyvm!byuvax!hallidayd
From: hallidayd@yvax.byu.edu
Newsgroups: comp.lang.fortran
Subject: Re: Fortran 8x:  pointers and optimization
Message-ID: <664hallidayd@yvax.byu.edu>
Date: 28 Jun 89 21:10:41 GMT
Lines: 23

In message <2773@elxsi.UUCP> Bob Corbett (corbett@beatnix.UUCP) makes the
statements
>              Thus, adding pointers does not make optimization harder than
>the IDENTIFY statement would.  However, pointers offer more functionality
>than the IDENTITY statement.

The first statement has already been adressed (the ALIASing provided by the
ALIAS/IDENTIFY pair cannot be reIDENTIFYed in a subroutine, while that provided
by POINTERs can).  The second statement, that POINTERs offer more functionality
than the IDENTIFY is false if we are considering only the ALIASing of array
sections (POINTERs do provide the added functionality of recursive data
structures, which the ALIAS/IDANTIFY pair was never intended to do).  There is
no way for the POINTER syntax to ALIAS arbitrary, functionally related, array
elements as can be acomplished with ALIAS/IDENTIFY---try ALIASing the diagonal
of an array with the present proposed POINTER syntax, it can't be done (as at
least one other poster has stated).

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