alt Hacker NewsI too lamented the loss of HTML imports and ended up coming up with my own JavaScript library for it.
https://miragecraft.com/blog/replacing-html-imports
At the end of the day it’s not something trivial to implement at the HTML spec/parser level.
For relative links, how should the page doing the import handle them?
Do nothing and let it break, convert to absolute links, or remap it as a new relative link?
Should the include be done synchronously or asynchronously?
The big benefit of traditional server side includes is that its synchronous, thus simplifying logic for in-page JavaScript, but all browsers are trying to eliminate synchronous calls for speed, it’s hard to see them agreeing to add a new synchronous bottleneck.
Should it be CORS restricted? If it is then it blocks offline use (file:// protocol) which really kills its utility.
There are a lot of hurdles to it and it’s hard to get people to agree on the exact implementation, it might be best to leave it to JavaScript libraries.
Replies
Someone else made the same - https://github.com/Paul-Browne/HTMLInclude - but it's not been updated in 7 years, leaving questions. I'll try yours and theirs in due course. Err, and the fragment @HumanOstrich said elsewhere in comments.
My guess is that some or maybe all of your concerns should have been solved by CSS @import (https://developer.mozilla.org/en-US/docs/Web/CSS/@import) although, as I'm reading the first few lines of the linked article, those must appear near the top of a CSS file, so are significantly more restricted than an import that can appear in the middle of a document.