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All arrays can be adjustable?

    Date: Tue, 19 May 87 21:34 EDT
    From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>

	Date: Tue, 19 May 87 19:03:33 MDT
	From: sandra%orion@cs.utah.edu (Sandra J Loosemore)

	It's definitely wrong for make-array to randomly return adjustable arrays
	when the user doesn't specifically ask for them.  

    I disagree.  See below.

I mopstly agree with you, but the bottom of page 28 seems to imply that
you can make arrays which are not to be adjusted, and this is one of the
properties of simple arrays.

One use of a non-adjustable array might be when you know that the array
is big enough for your program, and if something which automatically
adjusts adjustable arrays tries to adjust your array to make it bigger,
that means your program is broken somehow.  Rather than letting the
array get grown until you run out of address space to discover this
error, it would be desirable to get an error when the array tried to get
bigger than the size you originally limited it to.  Why something like
this is tied up in the concept of "simple" arrays I don't know; it seems
that an array which is able to provide this service may be less simple
to implement in some implementations.  Maybe the concept of "simple" is
what is bogus?