class Prism::ElseNode

def ===(other)

comparing the value of locations. Locations are checked only for presence.
Implements case-equality for the node. This is effectively == but without 
def ===(other)
  other.is_a?(ElseNode) &&
    (else_keyword_loc.nil? == other.else_keyword_loc.nil?) &&
    (statements === other.statements) &&
    (end_keyword_loc.nil? == other.end_keyword_loc.nil?)
end