Represents reading a reference to a field in the previous match.
$' ^^
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 1065
def initialize(name, location)
@name = name
@location = location
end
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 1137
def self.type
:back_reference_read_node
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 tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 1071
def accept(visitor)
visitor.visit_back_reference_read_node(self)
end
def accept: (visitor: Visitor) -> void
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 1076
def child_nodes
[]
end
def child_nodes: () -> Array[nil | Node]
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 1086
def comment_targets
[]
end
def comment_targets: () -> Array[Node | Location]
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 1081
def compact_child_nodes
[]
end
def compact_child_nodes: () -> Array
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 1091
def copy(**params)
BackReferenceReadNode.new(
params.fetch(:name) { name },
params.fetch(:location) { location },
)
end
def copy: (**params) -> BackReferenceReadNode
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 1102
def deconstruct_keys(keys)
{ name: name, location: location }
end
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 1107
def inspect(inspector = NodeInspector.new)
inspector << inspector.header(self)
inspector << "└── name: #{name.inspect}\n"
inspector.to_str
end
def inspect(inspector: NodeInspector) -> String
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 1127
def type
:back_reference_read_node
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