[m-rev.] for review: merge successive switches on the same variable

[Zoltan Somogyi]

For review by anyone. The intent is to allow module_name_to_file_name_ext
in file_names.m to be implemented in terms of separate switches for handling
base file names and for computing directory paths, without loss of efficiency.
However, the compiler also contains several existing examples of such code,
some as written by us, and some created by other optimizations.

Zoltan.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Log.msw
Type: application/octet-stream
Size: 2034 bytes
Desc: not available
URL: <http://lists.mercurylang.org/archives/reviews/attachments/20230816/dba61d6c/attachment-0002.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: DIFF.msw
Type: application/octet-stream
Size: 48585 bytes
Desc: not available
URL: <http://lists.mercurylang.org/archives/reviews/attachments/20230816/dba61d6c/attachment-0003.obj>