Please extend `typeset -U'

[Fung-Chai Lim <fclim@xxxxxxxxxxxxxx>]

Hi,

Currently, `typeset -U' only works for arrays and special parameters
known to zsh.

Many programs use PATH-like environmental variables; eg, GNU info
(INFOPATH), Sun's dynamic linker (LD_LIBRARY_PATH).

It would be nice if `typeset -U' also works for these var as well.

However, it is not possible to know beforehand what programs are
out there in the world, and the env-var names that they use.

So, how about if the name of the env-var has a `PATH' suffix,
`typeset -U' would treat the env-var as special?

Or, better yet, a new `set -D var' to indicate that `var' has a
dual:
	set -AD var ==> the dual is VAR
	set -D  VAR ==> the dual is var
The lowercase version is an array while the uppercase variable is
a colon-separated list of words.

Thanks.

Regards,
fclim.