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Article #21288Re: Bliss
From: jn... Joseph M. Newcomer
Date: Thu, 23 Apr 1992 22:48
Date: Thu, 23 Apr 1992 22:48
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1774 bytes
For those who don't know Bliss, here's a quick recap of the language:
In Bliss, a name /uniformly/ represented an address. Thus "A" was the
address of variable "A", whether static or on the stack. To get the
/value/ of "A", it had to be preceded by a dereference operator, which
was ".". So incrementing the value of "A" was done by "A=.A+1;" Although
the dot was chosen because it was small and unobtrusive, this meant that
it was easily missed in reading a listing, especially if the printer
ribbon (remember printers that had ribbons instead of toner cartridges?)
was marginal.
The canonical error in Bliss, especially for those transitioning from
traditional languages, was a "dot error", meaning the programmer forgot
to put the necessary dot in.
One day, Phil Karlton (CMU->Xerox->DEC) came to me and said "Well, I just
made my first dot error in SAIL". Now SAIL was an Algol-derived language.
It didn't even HAVE a "dot" operator! Naturally I said something like
"Sure, tell me another".
Phil said "Yes, it was the dot which goes over the comma which
terminates a comment". SAIL used the Algol syntax for comments:
"comment ... ;". What he had written was "comment ... ," and the next
statement was absorbed into the comment.
joe
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Path: mbox-mo1.pugleaf.net!sparky!uunet!cs.utexas.edu!rutgers!rochester!cantaloupe.srv.cs.cmu.edu!crabapple.srv.cs.cmu.edu!andrew.cmu.edu!jn11+ From: jn...@andrew.cmu.edu (Joseph M. Newcomer) Newsgroups: alt.folklore.computers Subject: Re: Bliss Message-ID: <cdxnv6200VsaA=uoYV@andrew.cmu.edu> Date: 23 Apr 92 22:48:38 GMT Organization: Carnegie Mellon, Pittsburgh, PA Lines: 25 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit