Class Sass::Selector::Universal
In: lib/sass/selector.rb
Parent: Simple

A universal selector (`*` in CSS).

Methods

new   to_a   unify  

Attributes

namespace  [R]  The selector namespace. `nil` means the default namespace, `[""]` means no namespace, `["*"]` means any namespace.

@return [Array<String, Sass::Script::Node>, nil]

Public Class methods

@param namespace [Array<String, Sass::Script::Node>, nil] See \{namespace}

[Source]

    # File lib/sass/selector.rb, line 95
95:       def initialize(namespace)
96:         @namespace = namespace
97:       end

Public Instance methods

@see Selector#to_a

[Source]

     # File lib/sass/selector.rb, line 100
100:       def to_a
101:         @namespace ? @namespace + ["|*"] : ["*"]
102:       end

Unification of a universal selector is somewhat complicated, especially when a namespace is specified. If there is no namespace specified or any namespace is specified (namespace `"*"`), then `sel` is returned without change (unless it‘s empty, in which case `"*"` is required).

If a namespace is specified but `sel` does not specify a namespace, then the given namespace is applied to `sel`, either by adding this {Universal} selector or applying this namespace to an existing {Element} selector.

If both this selector and `sel` specify namespaces, those namespaces are unified via {Simple#unify_namespaces} and the unified namespace is used, if possible.

@todo There are lots of cases that this documentation specifies;

  make sure we thoroughly test **all of them**.

@todo Keep track of whether a default namespace has been declared

  and handle namespace-unspecified selectors accordingly.

@todo If any branch of a CommaSequence ends up being just `"*"`,

  then all other branches should be eliminated

@see Selector#unify

[Source]

     # File lib/sass/selector.rb, line 129
129:       def unify(sels)
130:         name =
131:           case sels.first
132:           when Universal; :universal
133:           when Element; sels.first.name
134:           else
135:             return [self] + sels unless namespace.nil? || namespace == ['*']
136:             return sels unless sels.empty?
137:             return [self]
138:           end
139: 
140:         ns, accept = unify_namespaces(namespace, sels.first.namespace)
141:         return unless accept
142:         [name == :universal ? Universal.new(ns) : Element.new(name, ns)] + sels[1..-1]
143:       end

[Validate]