[texdoc] Deprecated stuff

[Manuel Pégourié-Gonnard]

Hi again,

Just for information, there a few options in texdoc that I decided to declare
deprecated for various reasons. Below is a short listing of them, but before
here is what I plan to do with them. Currently, every deprecated option has
stopped being documented, ad triggers a warning like

texdoc warning: Command-line options -a, --alias, -A, --noalias, as well as
texdoc warning: configuration item alias_switch, are deprecated
texdoc warning: and will soon be removed.
texdoc warning: Please protest on the texdoc mailing list if you need it.

I intend to keep the options working (besides the warning) until at least the
release of TL10, wait a few month more, so that I can be assured that enough
people are using a version of texdoc that produces the warnings, and then
actually remove support for these options, unless of course if somebody protests.

Now, the deprecated things are:

1. The ability to disable all aliasing by command-line switches or a
configuration file directive. However, it is (and will remain) possible to
prevent aliasing on a particular name by using 'stopalias NAME' in one's
configuration file (in case someone disagrees with the default aliases). The
reason for this option was that aliases were "hiding" other results, but this is
no more true since 0.60. Moreover, the searching mechanism is now quite
sophisticated, so it doesn't make a lot of sense to disable aliases while
keeping the other "goodies" on. So I want to remove this option because I think
it is useless; this will simplify things.

2. Regex mode (look for NAME as a pattern). This mode doesn't fit at all the new
search mechanisms. I doubt anyone is actually using it (it was Lua regexes, no
standard regexes). Besides, it makes for a lot of special cases in the code.

3. The -e, --extensions command-line option. The ext_list directive in
configuration files will remain. Changing the list of extensions on the command
line was probably useful for allowing any extension in regex mode, but now I
think it is useless. Also, the companion directive badext_list does not have an
associated command-line option, and I don't want to introduce one either.

Besides, the old environment variables used by all (known to me) versions of
texdoc are still recognised without issuing a warning, and the old name --search
for --showall (issuing a warning) are kept, and I plan to keep them probably
forever, as they do not clutter the interface nor the code.

Comments welcome, either on the list of options to be removed, or on the planned
removal process.

Thanks,
Manuel.