class Prism::FalseNode
Represents the use of the literal ‘false` keyword.
false ^^^^^
Public Class Methods
def initialize: (Location
location) -> void
# File lib/prism/node.rb, line 6548 def initialize(source, location) @source = source @newline = false @location = location 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 6618 def self.type :false_node end
Public Instance Methods
def accept: (Visitor
visitor) -> void
# File lib/prism/node.rb, line 6555 def accept(visitor) visitor.visit_false_node(self) end
def child_nodes
: () -> Array[nil | Node]
# File lib/prism/node.rb, line 6560 def child_nodes [] end
def comment_targets
: () -> Array[Node | Location]
# File lib/prism/node.rb, line 6570 def comment_targets [] #: Array[Prism::node | Location] end
def compact_child_nodes
: () -> Array
# File lib/prism/node.rb, line 6565 def compact_child_nodes [] end
def deconstruct_keys
: (Array keys) -> { location: Location
}
# File lib/prism/node.rb, line 6583 def deconstruct_keys(keys) { location: location } end
def inspect(NodeInspector inspector) -> String
# File lib/prism/node.rb, line 6589 def inspect(inspector = NodeInspector.new) inspector << inspector.header(self) inspector.to_str 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 6608 def type :false_node end