From f114f14b8b351c58103bc0f55f69778175ab57b6 Mon Sep 17 00:00:00 2001
From: Michael Orlitzky <michael@orlitzky.com>
Date: Sun, 15 Sep 2019 20:19:16 -0400
Subject: [PATCH] Add index support.

---
 GNUmakefile  | 23 +++++++++++++++++++++++
 examples.tex | 13 ++++++++++---
 2 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/GNUmakefile b/GNUmakefile
index a248258..a2e2ec2 100644
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -36,6 +36,8 @@ MJOTEX += mjo-theorem-star.tex mjo-topology.tex mjo.bst
 SAGE_LISTING_SRCS = $(wildcard sage_listings/*.listing)
 SAGE_LISTING_DSTS = $(patsubst %.listing,%.py,$(SAGE_LISTING_SRCS))
 
+INDICES = $(PN)
+
 # Use kpsewhich (from the kpathsea suite) to find the absolute paths
 # of the bibtex/mjotex files listed in in $(BIBS)/$(MJOTEX). The SRCS
 # variable should contain all (Bib)TeX source files for the document.
@@ -52,6 +54,12 @@ ifdef SAGE_LISTING_DSTS
 SRCS += $(SAGE_LISTING_DSTS)
 endif
 
+ifdef INDICES
+INDEX_SRCS = $(addsuffix .idx,$(INDICES))
+INDEX_DSTS = $(addsuffix .ind,$(INDICES))
+SRCS += $(INDEX_DSTS)
+endif
+
 # The first target is the default, so put the PDF document first.
 #
 # This voodoo is all designed to find a "fixed point" of calling
@@ -112,6 +120,21 @@ $(PN).aux: $(SRCS)
 	$(LATEX) $(PN).tex
 
 
+ifdef INDICES
+# We need to be able to build the index source files without involving
+# the main $(PN).pdf rule, in order to avoid a chicken-and-egg problem.
+# This is similar to the $(PN).aux rule above, except that an index is
+# optional and there might be more than one of them.
+$(INDEX_SRCS): $(PN).tex
+	$(LATEX) $(PN).tex
+endif
+
+ifdef INDICES
+# Create real indices from source files by running "makeindex" on them.
+%.ind: %.idx
+	makeindex $<
+endif
+
 # The pipe below indicates an "order-only dependency" on the aux file.
 # Without it, every compilation of $(PN).tex would produce a new
 # $(PN).aux, and thus $(PN).bbl would be rebuilt. This in turn causes
diff --git a/examples.tex b/examples.tex
index 07db38e..4005cdd 100644
--- a/examples.tex
+++ b/examples.tex
@@ -5,15 +5,20 @@
 \usepackage[nonumberlist]{glossaries}
 \makenoidxglossaries
 
+% If you want an index, we can do that too. You'll need to define
+% the "INDICES" variable in the GNUmakefile, though.
+\usepackage{makeidx}
+\makeindex
+
 \usepackage{mjotex}
 \usepackage{mathtools}
 
 \begin{document}
 
   \begin{section}{Algebra}
-    If $R$ is a commutative ring, then $\polyring{R}{X,Y,Z}$ is a
-    multivariate polynomial ring with indeterminates $X$, $Y$, and
-    $Z$, and coefficients in $R$. If $R$ is a moreover an integral
+    If $R$ is a \index{commutative ring}, then $\polyring{R}{X,Y,Z}$
+    is a multivariate polynomial ring with indeterminates $X$, $Y$,
+    and $Z$, and coefficients in $R$. If $R$ is a moreover an integral
     domain, then its fraction field is $\Frac{R}$.
   \end{section}
 
@@ -329,4 +334,6 @@
   \setglossarystyle{listdotted}
   \glsaddall
   \printnoidxglossaries
+
+  \printindex
 \end{document}
-- 
2.44.2