Documented new built-in function vars().
Documented new formatting features: %s takes any type, and
'%(key)format' % dictionary.
Documented posixpath.expandvars().
diff --git a/Doc/lib/libppath.tex b/Doc/lib/libppath.tex
index e6430be..731d344 100644
--- a/Doc/lib/libppath.tex
+++ b/Doc/lib/libppath.tex
@@ -34,6 +34,14 @@
path does not begin with a tilde, the path is returned unchanged.
\end{funcdesc}
+\begin{funcdesc}{expandvars}{p}
+Return the argument with environment variables expanded. Substrings
+of the form \samp{\$\var{name}} or \samp{\$\{\var{name}\}} are
+replaced by the value of environment variable \var{name}. Malformed
+variable names and references to non-existing variables are left
+unchanged.
+\end{funcdesc}
+
\begin{funcdesc}{isabs}{p}
Return true if \var{p} is an absolute pathname (begins with a slash).
\end{funcdesc}