--- a/preamble.tex	Mon Oct 26 05:39:29 2009 +0000
+++ b/preamble.tex	Mon Oct 26 17:14:35 2009 +0000
@@ -117,6 +117,8 @@
 \newcommand{\qMod}{\qRing-\operatorname{Mod}}
 \newcommand{\ZMod}{\Integer-\operatorname{Mod}}
 
+\newcommand{\lmod}[1]{\leftidx{_{#1}}{\operatorname{mod}}{}}
+
 \def\bc{{\mathcal B}}
 
 \newcommand{\into}{\hookrightarrow}