Support attributes and separators

I wonder if maintainer would be open for at least angular-compatible list of supported selectors https://angular.io/api/core/Directive#selector:

`element-name`: Select by element name.
`.class`: Select by class name.
`[attribute]`: Select by attribute name.
`[attribute=value]`: Select by attribute name and value.
`:not(sub_selector)`: Select only if the element does not match the sub_selector.
`selector1, selector2`: Select if either selector1 or selector2 matches.