class Prism::SingletonClassNode
Represents a singleton class declaration involving the ‘class` keyword.
class << self end ^^^^^^^^^^^^^^^^^
Attributes
attr_reader body: Prism::node?
attr_reader expression: Prism::node
attr_reader locals: Array
Public Class Methods
def initialize: (Array locals, Location
class_keyword_loc
, Location
operator_loc
, Prism::node expression, Prism::node? body, Location
end_keyword_loc
, Location
location) -> void
# File lib/prism/node.rb, line 16613 def initialize(source, locals, class_keyword_loc, operator_loc, expression, body, end_keyword_loc, location) @source = source @newline = false @location = location @locals = locals @class_keyword_loc = class_keyword_loc @operator_loc = operator_loc @expression = expression @body = body @end_keyword_loc = end_keyword_loc end
Similar to type
, this method returns a symbol that you can use for splitting on the type of the node without having to do a long === chain. Note that like type
, it will still be slower than using == for a single class, but should be faster in a case statement or an array comparison.
def self.type: () -> Symbol
# File lib/prism/node.rb, line 16749 def self.type :singleton_class_node end
Public Instance Methods
def accept: (Visitor
visitor) -> void
# File lib/prism/node.rb, line 16626 def accept(visitor) visitor.visit_singleton_class_node(self) end
def child_nodes
: () -> Array[nil | Node]
# File lib/prism/node.rb, line 16631 def child_nodes [expression, body] end
def class_keyword
: () -> String
# File lib/prism/node.rb, line 16693 def class_keyword class_keyword_loc.slice end
attr_reader class_keyword_loc
: Location
# File lib/prism/node.rb, line 16665 def class_keyword_loc location = @class_keyword_loc return location if location.is_a?(Location) @class_keyword_loc = Location.new(source, location >> 32, location & 0xFFFFFFFF) end
def comment_targets
: () -> Array[Node | Location]
# File lib/prism/node.rb, line 16644 def comment_targets [class_keyword_loc, operator_loc, expression, *body, end_keyword_loc] #: Array[Prism::node | Location] end
def compact_child_nodes
: () -> Array
# File lib/prism/node.rb, line 16636 def compact_child_nodes compact = [] #: Array[Prism::node] compact << expression compact << body if body compact end
def copy: (?locals: Array, ?class_keyword_loc: Location
, ?operator_loc: Location
, ?expression: Prism::node, ?body: Prism::node?, ?end_keyword_loc: Location
, ?location: Location
) -> SingletonClassNode
# File lib/prism/node.rb, line 16649 def copy(locals: self.locals, class_keyword_loc: self.class_keyword_loc, operator_loc: self.operator_loc, expression: self.expression, body: self.body, end_keyword_loc: self.end_keyword_loc, location: self.location) SingletonClassNode.new(source, locals, class_keyword_loc, operator_loc, expression, body, end_keyword_loc, location) end
def deconstruct_keys
: (Array keys) -> { locals: Array, class_keyword_loc
: Location
, operator_loc
: Location
, expression: Prism::node, body: Prism::node?, end_keyword_loc
: Location
, location: Location
}
# File lib/prism/node.rb, line 16657 def deconstruct_keys(keys) { locals: locals, class_keyword_loc: class_keyword_loc, operator_loc: operator_loc, expression: expression, body: body, end_keyword_loc: end_keyword_loc, location: location } end
def end_keyword
: () -> String
# File lib/prism/node.rb, line 16703 def end_keyword end_keyword_loc.slice end
attr_reader end_keyword_loc
: Location
# File lib/prism/node.rb, line 16685 def end_keyword_loc location = @end_keyword_loc return location if location.is_a?(Location) @end_keyword_loc = Location.new(source, location >> 32, location & 0xFFFFFFFF) end
def inspect(NodeInspector inspector) -> String
# File lib/prism/node.rb, line 16708 def inspect(inspector = NodeInspector.new) inspector << inspector.header(self) inspector << "├── locals: #{locals.inspect}\n" inspector << "├── class_keyword_loc: #{inspector.location(class_keyword_loc)}\n" inspector << "├── operator_loc: #{inspector.location(operator_loc)}\n" inspector << "├── expression:\n" inspector << inspector.child_node(expression, "│ ") if (body = self.body).nil? inspector << "├── body: ∅\n" else inspector << "├── body:\n" inspector << body.inspect(inspector.child_inspector("│ ")).delete_prefix(inspector.prefix) end inspector << "└── end_keyword_loc: #{inspector.location(end_keyword_loc)}\n" inspector.to_str end
def operator: () -> String
# File lib/prism/node.rb, line 16698 def operator operator_loc.slice end
attr_reader operator_loc
: Location
# File lib/prism/node.rb, line 16672 def operator_loc location = @operator_loc return location if location.is_a?(Location) @operator_loc = Location.new(source, location >> 32, location & 0xFFFFFFFF) end
Sometimes you want to check an instance of a node against a list of classes to see what kind of behavior to perform. Usually this is done by calling ‘[cls1, cls2].include?(node.class)` or putting the node into a case statement and doing `case node; when cls1; when cls2; end`. Both of these approaches are relatively slow because of the constant lookups, method calls, and/or array allocations.
Instead, you can call type
, which will return to you a symbol that you can use for comparison. This is faster than the other approaches because it uses a single integer comparison, but also because if you’re on CRuby you can take advantage of the fact that case statements with all symbol keys will use a jump table.
def type: () -> Symbol
# File lib/prism/node.rb, line 16739 def type :singleton_class_node end