The package extends the LaTeX labelling system: whenever a
label is set, the values of counters (selected by the user) are
recorded, along with the label. The value of these counters can
be recalled with a command similar to \pageref. The package
also adds commands \s[name]ref (for each counter [name] that
the user has selected); these commands display something only
if the value of the [name] counter is changed from when the
label was set. Many commands are provided to serve as a macro
programming environment for using the extended labels.
