Namespace per block.

[chriseppstein]

RFC: https://github.com/linkedin/css-blocks/issues/332

CSS Changes

• [x] The class selector will now be defined as selecting an attribute named class in the namespace of the block. (conceptual change, not requiring any stylesheet parsing changes at this time).
• [x] The default namespace for the attribute selector will be dom attributes in the namespace of the block. Therefore the state| namespace in the state attribute selector is no longer needed.
• [x] Global states are accessed via the attribute namespace instead of a fake tag name.
• [ ] The :scope selector will select an element with the attribute of scope that is in the namespace of the block.
• [x] States named "scope" will no longer be allowed.
• [x] non-block namespaces will be handled by registering common names of html, svg, and math and making them forbidden names for blocks.
• [ ] Other non-block namespaces can be registered through configuration.

Handlebars Template Syntax Changes

• [x] The namespace identifier for the default block associated with the template is block.
• [ ] If no element has an attribute of block:scope then it is automatically assigned to the template's root element.
• [x] Instead of class="foo other-block.bar" we would now write block:class="foo" other-block:class="bar".
• [x] The class attribute in html namespace is forbidden. (Later we can add configuration to allow it.)

Documentation Changes

• [ ] Document namespace concept in tutorials/readmes.
• [x] Website syntax updates.

[amiller-gh]

One more item to add to the TODO list: Make the word block a reserved word (if it's not already... I don't think it is).

Because you reference the "default" exported block as block, the compiler should throw if you try to @export (whatever as block ) from "wherever.block.css".

[amiller-gh]

Alt: You can just change the keyword default to block for the import/export parser.

This may be confusing for those coming from JavaScript world though – would not recommend.