X-Git-Url: http://gitweb.michael.orlitzky.com/?a=blobdiff_plain;f=mjo-arrow.tex;h=60530cb71020f3902e3b4c11f9a6498814241f5e;hb=6ee5658942c8662c360f0b1fd47dca460f761f48;hp=8b44ded1753eb175124ed71fa73ad4e5ec9b35e5;hpb=987368c596bfe23dbcbaf5260a0d7011c9d3fc1e;p=mjotex.git

diff --git a/mjo-arrow.tex b/mjo-arrow.tex
index 8b44ded..60530cb 100644
--- a/mjo-arrow.tex
+++ b/mjo-arrow.tex
@@ -1,8 +1,15 @@
 %
 % Things dealing with arrows in a category. Or functions, basically.
 %
+\ifx\havemjoarrow\undefined
+\def\havemjoarrow{1}
 
-\input{mjo-common}
+
+\input{mjo-common} % for \of, at least.
+
+\ifx\operatorname\undefined
+  \usepackage{amsopn}
+\fi
 
 % The identity operator/arrow on its argument.
 \newcommand*{\identity}[1]{ \operatorname{id}_{{#1}} }
@@ -16,3 +23,6 @@
 
 % The preimage of the second argument (a set) under the first (a function).
 \newcommand*{\preimage}[2]{ #1^{-1}\of{#2} }
+
+
+\fi