diff -r 8f2749152f1e -r 4796f424cf12 style.sty
--- a/style.sty	Wed Oct 29 19:36:15 2014 +0000
+++ b/style.sty	Wed Oct 29 21:58:08 2014 +0000
@@ -10,3 +10,19 @@
 
 \newcommand{\dn}{\stackrel{\mbox{\scriptsize def}}{=}}%
 \definecolor{codegray}{gray}{0.9}
+
+\newcommand\grid[1]{%
+\begin{tikzpicture}[baseline=(char.base)]
+  \path[use as bounding box]
+    (0,0) rectangle (1em,1em);
+  \draw[red!50, fill=red!20]
+    (0,0) rectangle (1em,1em);
+  \node[inner sep=1pt,anchor=base west]
+    (char) at (0em,\gridraiseamount) {#1};
+\end{tikzpicture}}
+\newcommand\gridraiseamount{0.12em}
+
+\makeatletter
+\newcommand\Grid[1]{%
+  \@tfor\z:=#1\do{\grid{\z}}}
+\makeatother