From 5c1a943a2ae3886693c0361084239aef9da3551c Mon Sep 17 00:00:00 2001
From: Michael Orlitzky <michael@orlitzky.com>
Date: Tue, 8 Mar 2016 19:54:33 -0500
Subject: [PATCH] Add mjo-misc and mjo-arrow files.

---
 makefile      |  6 +++---
 mjo-arrow.tex | 10 ++++++++++
 mjo-misc.tex  | 10 ++++++++++
 mjotex.sty    |  2 ++
 4 files changed, 25 insertions(+), 3 deletions(-)
 create mode 100644 mjo-arrow.tex
 create mode 100644 mjo-misc.tex

diff --git a/makefile b/makefile
index af651c6..57a4932 100644
--- a/makefile
+++ b/makefile
@@ -14,9 +14,9 @@ BIBS = references.bib
 
 # A space-separated list of the mjotex files that you use. The path to
 # mjotex must be contain in your $TEXINPUTS environment variable.
-MJOTEX  = mjo-algorithm.tex mjo-common.tex mjo-cone.tex mjo-convex.tex
-MJOTEX += mjo-font.tex mjo-linear_algebra.tex mjo-proof_by_cases.tex
-MJOTEX += mjo-theorem.tex mjo-topology.tex
+MJOTEX  = mjo-algorithm.tex mjo-arrow.tex mjo-common.tex mjo-cone.tex
+MJOTEX += mjo-convex.tex mjo-font.tex mjo-linear_algebra.tex mjo-misc.tex
+MJOTEX += mjo-proof_by_cases.tex mjo-theorem.tex mjo-topology.tex
 
 # Use kpsewhich (from the kpathsea suite) to find the absolute paths
 # of the bibtex/mjotex files listed in in $(BIBS)/$(MJOTEX). The SRCS
diff --git a/mjo-arrow.tex b/mjo-arrow.tex
new file mode 100644
index 0000000..3ae2daa
--- /dev/null
+++ b/mjo-arrow.tex
@@ -0,0 +1,10 @@
+%
+% Things dealing with arrows in a category. Or functions, basically.
+%
+
+% The identity operator/arrow on its argument.
+\newcommand*{\identity}[1]{ \operatorname{id}_{{#1}} }
+
+% The composition of two arrows/functions. For example, the
+% composition of g with f is \compose{g}{f}\of{x} === g\of{f\of{x}}.
+\newcommand*{\compose}[2]{ {#1} \circ {#2} }
diff --git a/mjo-misc.tex b/mjo-misc.tex
new file mode 100644
index 0000000..3d8a406
--- /dev/null
+++ b/mjo-misc.tex
@@ -0,0 +1,10 @@
+%
+% Things that fit absolutely nowhere else.
+%
+
+\usepackage{amsmath}
+
+% The cardinality of a set. The |X| notation conflicts with the
+% absolute value, and the meaning of card(X) is clear at once, so we
+% prefer the latter.
+\newcommand*{\card}[1]{ \operatorname{card} \of{{#1}} }
diff --git a/mjotex.sty b/mjotex.sty
index 5b89cd7..0d90d92 100644
--- a/mjotex.sty
+++ b/mjotex.sty
@@ -1,9 +1,11 @@
 \input{mjo-algorithm}
+\input{mjo-arrow}
 \input{mjo-common}
 \input{mjo-cone}
 \input{mjo-convex}
 \input{mjo-font}
 \input{mjo-linear_algebra}
+\input{mjo-misc}
 \input{mjo-proof_by_cases}
 \input{mjo-theorem}
 \input{mjo-topology}
-- 
2.43.2