class SyntaxTree::Parser

def on_fndptn(constant, left, values, right)

) -> FndPtn
VarField right
Array[untyped] values,
VarField left,
(nil | untyped) constant,
on_fndptn: (
:call-seq: 
def on_fndptn(constant, left, values, right)
  # The left and right of a find pattern are always going to be splats, so
  # we're going to consume the * operators and use their location
  # information to extend the location of the splats.
  right, left =
    [right, left].map do |node|
      operator = consume_operator(:*)
      location =
        if node.value
          operator.location.to(node.location)
        else
          operator.location
        end
      node.copy(location: location)
    end
  # The opening of this find pattern is either going to be a left bracket, a
  # right left parenthesis, or the left splat. We're going to use this to
  # determine how to find the closing of the pattern, as well as determining
  # the location of the node.
  opening = find_token(LBracket) || find_token(LParen) || left
  # The closing is based on the opening, which is either the matched
  # punctuation or the right splat.
  closing =
    case opening
    when LBracket
      tokens.delete(opening)
      consume_token(RBracket)
    when LParen
      tokens.delete(opening)
      consume_token(RParen)
    else
      right
    end
  FndPtn.new(
    constant: constant,
    left: left,
    values: values,
    right: right,
    location: (constant || opening).location.to(closing.location)
  )
end