class SyntaxTree::Kw

then the contents of the symbol node will contain a Kw node.
:if
will use a Kw, so if you use a keyword in a symbol literal for instance:
for the end. Note that anything that matches the list of keywords in Ruby
In the above example, there would be two Kw nodes: one for the if and one
end
if value
tree, so you end up seeing it quite a lot.
Kw represents the use of a keyword. It can be almost anywhere in the syntax

def ===(other) 

def ===(other)
  other.is_a?(Kw) && value === other.value
end

def accept(visitor) 

def accept(visitor)
  visitor.visit_kw(self)
end

def child_nodes 

def child_nodes
  []
end

def copy(value: nil, location: nil) 

def copy(value: nil, location: nil)
  node =
    Kw.new(value: value || self.value, location: location || self.location)
  node.comments.concat(comments.map(&:copy))
  node
end

def deconstruct_keys(_keys) 

def deconstruct_keys(_keys)
  { value: value, location: location, comments: comments }
end

def format(q) 

def format(q)
  q.text(value)
end

def initialize(value:, location:) 

def initialize(value:, location:)
  @value = value
  @name = value.to_sym
  @location = location
  @comments = []
end