Pass through all slide shortcode params to section

Now slides can have ids and arbitrary data attributes, and a whitelist of valid attributes no longer needs to be maintained.

README.md

@@ -158,10 +158,10 @@ Like fragment but more terse - content is placed inline in a self-closing shortc
 
 #### slide shortcode
 
-The slide shortcode lets you set custom Reveal.js attributes for each slide - things like transition, background color and [much more](https://github.com/hakimel/reveal.js/#slide-attributes).
+The slide shortcode lets you set custom Reveal.js attributes for each slide - things like id, transition, background and [much more](https://github.com/hakimel/reveal.js/#slide-attributes).
 
 ```markdown
-{{% slide background="#FFF" transition="zoom" transition-speed="fast" %}}
+{{% slide id="hello" background="#FFF" transition="zoom" transition-speed="fast" %}}
 
 # Hello, world!
 

exampleSite/content/home/shortcodes/slide.md

@@ -4,18 +4,18 @@ weight = 34
 
 ## Slide
 
-Customize individual slide parameters like background color and transition.
+Customize individual slide attributes like id, background color and transition. Use the same keys as Reveal.js but omit the 'data-' prefix.
 
-[See all slide params](https://github.com/hakimel/reveal.js#slide-backgrounds)
+[See more attributes](https://github.com/hakimel/reveal.js#slide-attributes)
 
 ---
 
-{{% slide transition="zoom" transition-speed="fast" %}}
+{{% slide id="custom-1" transition="zoom" transition-speed="fast" %}}
 
 ## Custom slide 1
 
 ```
-{{%/* slide transition="zoom" transition-speed="fast" */%}}
+{{%/* slide id="custom-1" transition="zoom" transition-speed="fast" */%}}
 
 ## Custom slide 1
 
@@ -26,12 +26,12 @@ Customize individual slide parameters like background color and transition.
 
 ---
 
-{{% slide background-color="#FF4081" %}}
+{{% slide id="custom-2" background="#FF4081" %}}
 
 ## Custom slide 2
 
 ```
-{{%/* slide background-color="#FF4081" */%}}
+{{%/* slide id="custom-2" background="#FF4081" */%}}
 
 ## Custom slide 2
 
@@ -42,6 +42,19 @@ Customize individual slide parameters like background color and transition.
 
 ---
 
+💡 Tip: Setting a slide's `id` attribute makes it easy to link to from other parts of the presentation.
+
+<br>
+```markdown
+Go to [custom slide 1](#custom-1)
+```
+
+<small>
+Go to [custom slide 1](#custom-1)
+</small>
+
+---
+
 {{% section %}}
 
 {{% slide content="home.example" /%}}

layouts/shortcodes/slide.html

@@ -12,12 +12,16 @@
     {{- $scratch.Add "slides" . -}}
   {{- end -}}
 {{- end -}}
-{{- $attributes := slice "background-color" "background-image" "background-size" "background-position" "background-repeat" "transition" "transition-speed" "background-iframe" "background-interactive" "background-video" "background-video-loop" "background-video-muted" -}}
 {{- $params := . -}}
+{{- $noPrefix := slice "id" -}}
+{{- $noOutput := slice "content" -}}
 {{- range .Scratch.Get "slides" }}
 <section data-noprocess data-shortcode-slide
-  {{- range $attribute := $attributes -}}
-    {{- with $params.Get $attribute }} data-{{ $attribute | safeHTMLAttr }}="{{ . }}"{{ end -}}
+  {{- range $key, $value := $.Params -}}
+    {{- if not (in $noOutput $key) -}}
+      {{- $attrName := cond (in $noPrefix $key) $key (delimit (slice "data" $key) "-") }}
+      {{ $attrName | safeHTMLAttr }}="{{ $value }}"
+    {{- end -}}
   {{- end -}}>
   {{ . | safeHTML }}
 </section>