From 769943e0276228d2db9a7f89cd057d491eea4716 Mon Sep 17 00:00:00 2001
From: Michael Orlitzky <michael@orlitzky.com>
Date: Tue, 25 Apr 2023 11:30:48 -0400
Subject: [PATCH] beamerthemeUMBC.sty: allow partless sections.

Sometimes having a full Part : Section hierarchy is too much. We can
now use only sections, and the part titles (and the colon separators)
will be gracefully omitted.
---
 beamerthemeUMBC.sty | 23 ++++++++++++++++++++---
 1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/beamerthemeUMBC.sty b/beamerthemeUMBC.sty
index a376fd5..6824ac8 100644
--- a/beamerthemeUMBC.sty
+++ b/beamerthemeUMBC.sty
@@ -10,10 +10,21 @@
 % Create a slide introducing new sections.
 \AtBeginSection[]{
   \begin{frame}
-    \frametitle{Part \thepart, Section \thesection}
+    \frametitle{
+      \ifx\insertpart\@empty%
+      \else%
+      Part \thepart, %
+      \fi%
+      Section \thesection
+    }
     \vfill
     \begin{center}
-      \usebeamerfont{title}\insertpart: \insertsectionhead\par%
+      \usebeamerfont{title}
+      \ifx\insertpart\@empty%
+      \else%
+      \insertpart: %
+      \fi%
+      \insertsectionhead\par%
     \end{center}
     \vfill
   \end{frame}
@@ -21,7 +32,13 @@
 
 % Define a new ``partsecframe'' environment that uses a default frame
 % title of ``<part>: <section>'' when no other frame title is given.
-\newenvironment{partsecframe}[1][\insertpart: \insertsectionhead]
+\newenvironment{partsecframe}[1][%
+  \ifx\insertpart\@empty%
+  \else%
+  \insertpart: %
+  \fi%
+  \insertsectionhead%
+]
   {\begin{frame}{#1}}
   {\end{frame}}
 
-- 
2.43.2