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Re: upper and lower case
- Subject: Re: upper and lower case
- From: CSVAX.jkf at Berkeley
- Date: Sun ,1 Feb 81 00:11:44 EDT
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
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.
. ... 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?