I’m sure I don’t have the expertise to understand the finer nuances of this, but I like the spirit:
The HTML5 specification defines the template element but doesn’t provide a native mechanism to instantiate it with some parts of it substituted, conditionally included, or repeated based on JavaScript values — as popular JavaScript frameworks such as Ember.js and Angular allow. As a consequence, there are many incompatible template syntaxes and semantics to do substitution and conditionals within templates — making it hard for web developers to combine otherwise reusable components when they use different templating libraries.
Whilst previously we all decided to focus on shadow DOM and the custom-elements API first, we think the time is right — now that shadow DOM and custom-elements API have been shipping in Safari and Chrome and are in development in Firefox — to propose and standardize an API to instantiate HTML templates.
Let the frameworks compete on speed and developer convenience in other ways.
