From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,4bc0e5c544f4d1eb X-Google-Attributes: gid103376,public From: mheaney@ni.net (Matthew Heaney) Subject: Re: question on variant record Date: 1996/11/15 Message-ID: #1/1 X-Deja-AN: 196776980 references: content-type: text/plain; charset=ISO-8859-1 organization: Estormza Software mime-version: 1.0 newsgroups: comp.lang.ada Date: 1996-11-15T00:00:00+00:00 List-Id: In article , dewar@merv.cs.nyu.edu (Robert Dewar) wrote: >Matthew Heany said > >"The technical term is "discriminant," not "tag field." And technically, a >"variant record" is a discriminant record only with a variant part (case >statement). You probably meant "discriminant record" in your subject line." > >variant record is a perfectly good term, see for example para 35 of the >introduction to the RM: > >35 Record, task, and protected types may have special components called >discriminants which parameterize the type. Variant record structures that >depend on the values of discriminants can be defined within a record type. > > >variant_part is a perfectly good syntactic term, so the term variant >record is a perfectly reasonable one, it means a record with a variant >part. > >The other term is discriminaTED record, which is a record type with >discriminants. Note that all variant records have discriminants, but >not all records with discriminants have variant parts, so variant record >is a useful term. > >P.S. the term discriminant record is not used in the RM. I stand corrected. Thank you for clarifying this. M. -------------------------------------------------------------------- Matthew Heaney Software Development Consultant mheaney@ni.net (818) 985-1271