Jekyll multiple pages using the same template - html

Question

I'm aware you can use _layouts and in your pages do something like
---
layout: some_layout
title: Home
---
So say I have 20 pages. All using the same template but slightly different content and stuff inside.
Instead of creating 20 different pages.html files with different names and different permalinks.
Is there a way to create 1 page.html and based on the permalink change what's inside the {{ content }}?

Answer 1

Just create your-slug.md files. Let them all use the same layout, like this:
---
layout: some_layout
title: Your title
---
In the layout file (some_layout.html) you put some logic, like this:
{% if page.url contains '/your-slug' %}Put this on the screen.{% endif %}

Answer 2

You could organize the 20 pages under a collection and assign defaults on the collection.
For example, say your collection is labelled docs, then all those 20 pages need to be placed inside a directory named _docs, at the root of your source directory. Following that configure your collection to use the layout some_layout for its documents.
# _config.yml
# enable rendering on your collection(s)
collections:
docs:
output: true
another_collection:
output: true
# set defaults on your collection. (note the indentation..)
defaults:
-
scope:
type: docs
path: _docs
values:
layout: some_layout # The layout for this collections' files
-
scope:
type: another_collection
[...]

Answer 3

I have not tried this yet, but there is a closed github issue: https://github.com/jekyll/jekyll/issues/16
There are suggestions to write/use a jekyll plugin like the ones below. These are links from the issue and their state is unknown to me.
https://github.com/ixti/ixti.github.io/blob/source/_plugins/categories.rb
https://github.com/rfelix/my_jekyll_extensions/tree/master/category_gen
how to write a plugin: https://jekyllrb.com/docs/plugins/