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Re: upper and lower case

To: gjc,hic,dlw
   Thank you for clearing up my ignorance of Maclisp and Lisp Machine lisp.
Gjc, you mentioned that PDP10 Maclisp has a mechanism for handling lower 
case print names.  Is this mechanism the same as described by dlw, that is 
do you have to escape lower case characters or can you just do a 
sstatus somethingorother?

   Enough practical questions, back to the discussion.  I can see that people 
are going to chose sides on this argument based on the operating system they 
are most familiar with.  When I was an undergraduate, I worked on a PDP10 
system whose file names (and thus command names) were all upper case.  
Life was simple for the programmer, he simply converted everything to upper 
case.  We could justify it by pointing out that 95% of our terminals were 
upper case only and thus we weren't going to put in code to handle the 
lower case terminals in a special way.  When I started using Unix, it 
seemed very strange to me to see everything in lower case but now that I am 
accustomed to it I can appreciate the advantages.  Certainly, with the 
added freedom of upper and lower case command names, there is a possibility 
of mass confusion if there are no standards.  HIC asked how many commands 
executed from the Unix shell use upper and lower case.  There are very few, 
and they use upper case for a purpose.  We have a simple mail handler 
called `mail' and a super mail handler called 'Mail' (this is probably 
similar to :mail and :rmail on ITS).  We have a simple spelling checker 
called `spell' and a more powerful one called `Spell'.  I have personalized 
my shell to understand that the commands `Cifplot' and `Caesar' refer 
to the development versions of the system programs `cifplot' and `caesar'.
I think that most people here would be very disappointed if all of the
sudden they couldn't use both cases.
    From: GJC
.  					... The strongest argument
    may be the following: lisp programmers "talk" about their programs,
    they do not dwell on how they look on paper, they do not visualize
    them in terms of characters. Spoken communication is much the same,
    capitalization and case do not get past the footlights, although
    good punctuation is very important.
Spoken communication is potentially much more powerful than written
communication.  Thus when you have to write down your program you 
need all the help you can get.   One way to get this power is to 
use different case characters.  To go back to the example in my previous
letter, just think of the difference between Z, Q, R and z, q, r in an 
algebra system.  There is a lot of information contained in the case
of the symbol.

  Another question, if you grind a file containing symbols like
Maclisp, MacLisp and MacLISP, do they all come out MACLISP?  If
you always write FooBar in your code, aren't you bothered when
this comes out FOOBAR in traces and prints?