Path: utzoo!attcan!uunet!zaphod.mps.ohio-state.edu!ncar!noao!arizona!gudeman
From: gudeman@cs.arizona.edu (David Gudeman)
Newsgroups: comp.lang.misc
Subject: Re: Answers, Chapter 1: TeX
Message-ID: <27028@megaron.cs.arizona.edu>
Date: 31 Oct 90 20:15:53 GMT
Organization: U of Arizona CS Dept, Tucson
Lines: 35

In article  <4464@lanl.gov> jlg@lanl.gov (Jim Giles) writes:
]
]Ok.  First _without_ the 'aliased' attribute:
]   ... arrays are a direct win over pointers (which is why
]   Fortran is usually faster than C on array intensive code).  Of
]   course, optimizing the arrays this way is unsafe unless the
]   loader checks all passed arguments to enforce the constraint that
]   distinct arrays are NOT aliased.

You are still comparing apples and oranges.  You are comparing
"arrays, assumed not to be aliased" with "pointers, assumed to be
aliased".

]Now _with_ the 'aliased' attribute:
]   (like the one I'm recommending), then pointers don't give you any
]   capability you don't already have _without_ them.  Pointers in such
]   a language are neither more powerful, more legible,...

This, of course, is a matter of opinion.  Maybe to clarify things, you
could post your definition of "pointer".  In particular, I'm
curious about how you think passing a pointer (C-style) is different
from passing an array.

]   ...  Using pointers to simulate these data types
]   (sequences for example) deprives the compiler of information which
]   _could_ be used to improve the performance of the code.

I'd also like to know what information this is.  Presumably a complete
definition of what you mean by "pointer" and "array" will make this
obvious.
-- 
					David Gudeman
Department of Computer Science
The University of Arizona        gudeman@cs.arizona.edu
Tucson, AZ 85721                 noao!arizona!gudeman