> We've lost a lot of expressiveness: what if we wanted to create a nested list again? We could make it a template macro, but we have to do extra work to call it inside itself, and suddently we have an extra language to learn.

Not that I’ve used jinja aside from some Ansible, I don’t get the second language part for templates or why templates are limiting? Even React’s syntax really isn’t that different from a template as you need to enclose JS expressions in curly braces right?

My favorite HTML server language is Elixir which has a Ruby flavored template engine called using `<%= some_func(@val) %>`. It’s only 4 “tags” [1]. Well maybe since it’s a functional language and everything is an expression the semantics are simpler, mainly limited to whether or not to return a value. Jinja probably is more difficult since Python control flow isn't an expression so you add another layer (probably same in Ruby, Java, etc). Calling functions is as easy as ensuring they’re in the scope of where it’s loaded (or just the current scope when using the ~E sigil. So in the first example encapsulating a sub-lists is just creating a function that returns a template. When compiled it’ll create functions that return IO lists so it’s pretty efficient too [2].

Given that, I prefer having HTML look like HTML.

1: https://hexdocs.pm/eex/EEx.html 2: https://edmz.org/personal/2016/09/06/phoenix_templates-_yup,...