[r6rs-discuss] Case-Sensitivity Optional, Case-Preservation Mandatory

[John Cowan]

Erich Rast scripsit:

> I submit that all implementations MUST be case-preserving under
> certain circumstances. Whatever is done to source code/data file input
> MUST preserve case information if (a) the implementation provides a way
> to retrieve the original symbols of the source data (i.e. the source
> data is not compiled to something else entirely anyway), and (b) the
> respective symbols are not mapped to another case explicitly.

With respect, that seems to me utterly incoherent as stated.  The essence
of case-insensitivity is that foo and FOO are the same symbol; that is,
when you "retrieve the original symbols of the source data" for these
two spellings, they are eq? as symbols.  How then can they be both eq?
and distinguishable?

Usually when we speak of case-preservation, we mean that the case of
the *defining* instance is preserved.  On the case-insensitive NTFS file
system, for example, the case used when a file is created is preserved.
Is that what you mean?

-- 
John Cowan  cowan at ccil.org  http://ccil.org/~cowan
In computer science, we stand on each other's feet.
        --Brian K. Reid