dynamic strings in help text

[Dan McMahill]

I have a configure.ac file which has some shell commands to set a 
variable which I want to later use in a help string.  The shell commands 
basically just enumerate modules contained in the source directory.


# some shell commands which give a value for the
# hid_guis variables

AC_MSG_CHECKING([for which gui to use])
AC_ARG_WITH([gui],
[  --with-gui=  Specify the GUI to use: $hid_guis],
[],
[with_gui=gtk]
)


This doesn't work for 2 reasons.

1)  The help string stuff ends up in configure before the code which 
sets hid_guis.

2)  The help string is printed with


cat <<\_AC_EOF

help text

AC_EOF

and the "\" bit prevents variable expansion.

Is there a simple way around this?

Thanks
-Dan