X-Git-Url: http://gitweb.michael.orlitzky.com/?p=mjotex.git;a=blobdiff_plain;f=mjo-common.tex;h=8ead1233ece6d100f632c6f390d391d7bd957142;hp=e59920181ae51081530fbe92cfad47b87ba5d387;hb=fc7cfa7f3d02715cb09eae2e1c6bc501dc2d8d50;hpb=21149d05f0bf33baecfe002704f8dd3d939951e7

diff --git a/mjo-common.tex b/mjo-common.tex
index e599201..8ead123 100644
--- a/mjo-common.tex
+++ b/mjo-common.tex
@@ -1,6 +1,9 @@
 %
 % Only the most commonly-used macros. Needed by everything else.
 %
+\ifx\havemjocommon\undefined
+\def\havemjocommon{1}
+
 
 % Needed for \mathbb.
 \usepackage{amsfonts}
@@ -8,7 +11,7 @@
 % Needed for \bigtimes.
 \usepackage{mathtools}
 
-% Place the argument in matching left/right parntheses.
+% Place the argument in matching left/right parentheses.
 \providecommand*{\of}[1]{ \left({#1}\right) }
 
 % Group terms using parentheses.
@@ -124,3 +127,14 @@
 \providecommand*{\cartprodmany}[3]{ \binopmany{\bigtimes}{#1}{#2}{#3} }
 \providecommand*{\directsummany}[3]{ \binopmany{\bigoplus}{#1}{#2}{#3} }
 \providecommand*{\unionmany}[3]{ \binopmany{\bigcup}{#1}{#2}{#3} }
+
+
+% The four standard (UNLESS YOU'RE FRENCH) types of intervals along
+% the real line.
+\providecommand*{\intervaloo}[2]{ \left({#1},{#2}\right) } % open-open
+\providecommand*{\intervaloc}[2]{ \left({#1},{#2}\right] } % open-closed
+\providecommand*{\intervalco}[2]{ \left[{#1},{#2}\right) } % closed-open
+\providecommand*{\intervalcc}[2]{ \left[{#1},{#2}\right] } % closed-closed
+
+
+\fi