Represents a node that is missing from the source and results in a syntax error.
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 11897
def initialize(location)
@location = location
end
def initialize: (location: Location
) -> void
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 11966
def self.type
:missing_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 11902
def accept(visitor)
visitor.visit_missing_node(self)
end
def accept: (visitor: Visitor
) -> void
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 11907
def child_nodes
[]
end
def child_nodes
: () -> Array[nil | Node]
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 11917
def comment_targets
[]
end
def comment_targets
: () -> Array[Node | Location]
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 11912
def compact_child_nodes
[]
end
def compact_child_nodes
: () -> Array
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 11922
def copy(**params)
MissingNode.new(
params.fetch(:location) { location },
)
end
def copy: (**params) -> MissingNode
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 11932
def deconstruct_keys(keys)
{ location: location }
end
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 11937
def inspect(inspector = NodeInspector.new)
inspector << inspector.header(self)
inspector.to_str
end
def inspect(inspector: NodeInspector) -> String
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 11956
def type
:missing_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