Subject: Re: Writing CLOS objects to a file portably?
From: Erik Naggum <erik@naggum.net>
Date: Sat, 22 Dec 2001 06:42:32 GMT
Newsgroups: comp.lang.lisp
Message-ID: <3217992151071959@naggum.net>

* Kevin Rosenberg
| You could you use the function array-element-type to retrieve the
| specialized element type.  The element-type could be stored and then
| loaded to recreate the array.  The only problem I see is the ANSI
| standard leaves the value of array-element-type as
| implementation-dependent.  So, you might get some supertype of the
| element-type.

  Yes, this might be little worrying.  Except for the predefined types
  bitvector and string, we rely on commonality of implementations, but one
  could imagine a situation where implementations A and B were such that
  they had no common types of specialized arrays and shipping data back and
  forth between them would be like calling upgraded-array-element-type on
  each implementation with the result from the other, converging on t as
  the element-type.  To avoid this problem, you would have to store the
  intended element-type, not the actual element-type.

///
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