Add not to mean !

[Keats]

In condition nodes.

Currently there's no way to indicate negation in if/elif.

For booleans we can do:

{% if my_bool == false %}

but that's obviously not ideal and doesn't work for truthy values (truthiness defined there https://github.com/Keats/tera/blob/master/src/context.rs#L86-L99)

We want to be able to express negation like so:

{% if not my_array %} // empty array will result in that if body rendering
{% if not username %} // empty string or null values will result in that if body rendering
{% if user and not user.is_admin %} // render if user exists but is not an admin

The not should be a keyword only used in the condition node but should be reserved globally as a Tera keyword in case we want to expand its use

[Keats]

@Robbepop I've seen your email but the comment doesn't appear in github for some reason.

I clarified the issue a bit more

[Keats]

Anyone working on that? @Robbepop ?