Case-sensitivity goals, policy and implementation

[ Dudley, Jeremy <Dudley_J@wrcplc.co.uk>, Mon, 11 Oct 2004 14:31:31 +0100]:
> > "In maths, I am used to case sensitivity. As a simple example, 'a'
> > being a vector and 'A' being a matrix. In programming, I loathe
> > case sensitivity. I want 'a' and 'A' to be the same, not a cause
> > for confusion; too often do I type something like 'COmmon' when I
> > want 'Common.' In a language that demands variable declaration
> > this can be picked up, at least to some extent.  Maxima does not
> > demand such an approach, so the risk of propagation of mistakes
> > seems too high."

(Chiming back in, again for myself:)

[Richard Fateman <fateman@cs.berkeley.edu>, Mon, 11 Oct 2004 08:07:19 -0700]:
> A flag to the reader program in Maxima that says:
> when I type in to the top level, convert all my
> characters to lower case.  Thus cOmMoN  would become
> common before processing. The output would be simply
> common.
> 
> The name of the flag might be
> downcase_all_input.   Or maybe  DoWNcASe_All_INPuT :)

ISTM that this approach suffers from the difficulty that you then
cannot know what setting the user prefers.  Say a case-sensitivist S
writes some Maxima code a case-insensitivist I wants to use it.  I can
only see the following possibilities:

- things break as S thought that x and X are different (seems most likely);

- I needs to do block(downcase_all_input: false, load("...")) and then
  ends up with a mixture of case-sensitivity and -insensitivity,
  however things are made to work; or

- S cannot count on x and X being separate symbols.

The other way round, if I writes some code to be used for S, we have
either

- things break as I had no reason to suspect that x and X are not the
  same (seems most likely);

- S needs to do block(downcase_all_input: true, load("...")) and then
  ends up with ugly all-lowercase[1] symbols; or

- I cannot count on x and X being the same.

Either way, this comes with considerable cost and is likely to hamper
the easy exchange of code; in addition, it seems this might make it
more difficult to call Maxima from Lisp as you have to worry about
calling $FOO or |$foo| etc - after all, Common Lisp is case
sensitive.  Seems like the worst of both worlds to me.

I personally do not care whether Maxima is case sensitive or not, but
mixing both is confusing and IMO certainly not worth the cost,
irrespective of a downcase_all_input flag.

Regards,

Albert.


[1] Actually, to facilitate using things from Lisp it should probably
    UPCASE the symbols.


> :Albert Reiner wrote:

Actually, no:  Jeremy Dudley wrote:

> >     [ Posting this on behalf of "Dudley, Jeremy" <Dudley_J@wrcplc.co.uk>,
> >       whose posting from Mon, 11 Oct 2004 14:31:31 +0100 was rejected: ]