Path: utzoo!utgpu!watserv1!watmath!att!linac!pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!samsung!uunet!cos!fetter
From: fetter@cos.com (Bob Fetter)
Newsgroups: comp.protocols.iso
Subject: Re: ASN.1 defn. is a grammar?
Keywords: ASN.1, grammar
Message-ID: <43252@cos.com>
Date: 4 Feb 91 04:55:42 GMT
References: <1991Jan31.165316.616@shl.com>
Reply-To: fetter@cos.UUCP (Bob Fetter)
Organization: Corporation for Open Systems, McLean, VA
Lines: 21


  That is a wonderful example of bad specification.

  You really should *not* rely on Constructed/Primitive as a clue to
determining the class of data.  Degenerating the tag down to it's base
Universal type should give you the rules for constructed/primitive, but
this path is based on manipulating the tag first, *then* worrying about
construction.

  If at all possible, the specification should be reworked to remove
this ambiquity.

  I can only hope that this isn't sprung from some standard, but is
based on a local use of ASN.1.

  As an aside chuckle, isn't Ada (tm) supposed to be *another* language
in which it's impossible to make an error, as it's so well specified? :-)

  But, if not, then that's what NIST OIW and EC EWOS is all about, I guess...

  -Bob-