mjo-arrow: add the constant function \const.

[mjotex.git] / mjo-algebra.tex

diff --git a/mjo-algebra.tex b/mjo-algebra.tex
index d70d9fd919fa1d39da8036953c03b3d52ce27426..0b8dc93c2df8ad9da5f2b911c61eb251bc8f6b43 100644 (file)
--- a/mjo-algebra.tex
+++ b/mjo-algebra.tex
@@ -1,5 +1,13 @@
-% Needed for \operatorname.
-\usepackage{amsopn}
+%
+% Abstract algebraic structures.
+%
+\ifx\havemjoalgebra\undefined
+\def\havemjoalgebra{1}
+
+
+\ifx\operatorname\undefined
+  \usepackage{amsopn}
+\fi
 
 % The fraction field of its argument, an integral domain. The name
 % "Frac" was chosen here instead of "Quot" because the latter
@@ -11,3 +19,6 @@
 % coefficients is the first argument and whose indeterminates (a
 % comma-separated list) are the second argumnt.
 \newcommand*{\polyring}[2]{{#1}\left[{#2}\right]}
+
+
+\fi