feat: slide number end

Author: xieby1

README.md

@@ -562,6 +562,38 @@ Example:
 reveal.sh README.md --toc=false
 ```
 
+# Slide Number End
+
+Slides after the specific slides
+
+can be excluded from the **total slide number**.
+
+---
+
+Think about a situation where,
+
+in your PhD defense,
+
+there are several **backup slides** at the end.
+
+You do not want them counted to the total slide number.
+
+## `.slide-count-end`
+
+Add `.slide-count-end` to the heading of the slide,
+
+```md
+# Heading {.slide-count-end}
+```
+
+## Example
+
+In this README, `.slide-count-end` is added to slide [QnA].
+
+Therefore, the slides after [QnA], like [Backup Slides]
+
+are not counted to total slide number
+
 # TOC (resident)
 
 See,
@@ -651,7 +683,7 @@ you can control how many TOC columns you have.
 * The default `toc-margin` is `0 0 0 0`
 * Thus a 3-column toc is presented.
 
-### 1-column TOC {.slide-count-end}
+### 1-column TOC
 
 Here is an example of 1-column TOC
 
@@ -660,10 +692,26 @@ toc-column-width: unset
 toc-margin: 0 400px
 ```
 
-# QnA
+# QnA {.slide-count-end}
 
 * Problems?
 * tips?
 * Advice?
 
 New issue and pull request is welcome!
+
+# Backup Slides
+
+Test the functionality of [Slide Number End].
+
+From this slide on,
+
+the total slide number ends counting.
+
+## Level-2 Backup Slides
+
+🐱
+
+## Another Level-2 Backup Slides
+
+🐈

bin/revealjs.sh

@@ -79,7 +79,6 @@ CMD=(
     "-V menu"
     "-V verticator"
     "-V showSlideNumber=all"
-    "-V slideNumber='c/t'"
     "--slide-level=6"
     # table of content
     "--toc"

share/markdown_revealjs/template.html

@@ -350,7 +350,17 @@ <h2 id="$idprefix$toc-title">$toc-title$</h2>
         // * h/v Horizontal / Vertical slide number
         // * c Flattened slide number, including both horizontal and vertical slides
         // * c/t Flattened slide number / total slides
-        slideNumber: '$slideNumber$',
+        slideNumber: slide => {
+            slideEndCount = document.getElementsByClassName("slide-count-end")[0]
+            // see reveal.js/js/controllers/slidenumber.js
+            // Offset the current slide number by 1 to make it 1-indexed
+            let horizontalOffset = slide && slide.dataset.visibility === 'uncounted' ? 0 : 1;
+            return [
+                Reveal.getSlidePastCount( slide ) + horizontalOffset,
+                '/',
+                Reveal.getSlidePastCount( slideEndCount ) + 1,
+            ];
+        },
 
         // 'all', 'print', or 'speaker'
         showSlideNumber: '$showSlideNumber$',