class Prism::DefinedNode

Represents the use of the ‘defined?` keyword.

defined?(a)
^^^^^^^^^^^

Attributes

value[R]

attr_reader value: Prism::node

Public Class Methods

new(source, lparen_loc, value, rparen_loc, keyword_loc, location) click to toggle source

def initialize: (Location? lparen_loc, Prism::node value, Location? rparen_loc, Location keyword_loc, Location location) -> void

# File prism/node.rb, line 6032
def initialize(source, lparen_loc, value, rparen_loc, keyword_loc, location)
  @source = source
  @location = location
  @lparen_loc = lparen_loc
  @value = value
  @rparen_loc = rparen_loc
  @keyword_loc = keyword_loc
end

type() click to toggle source

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 prism/node.rb, line 6154
def self.type
  :defined_node
end

Public Instance Methods

===(other) click to toggle source

Implements case-equality for the node. This is effectively == but without comparing the value of locations. Locations are checked only for presence.

# File prism/node.rb, line 6160
def ===(other)
  other.is_a?(DefinedNode) &&
    (lparen_loc.nil? == other.lparen_loc.nil?) &&
    (value === other.value) &&
    (rparen_loc.nil? == other.rparen_loc.nil?) &&
    (keyword_loc.nil? == other.keyword_loc.nil?)
end

accept(visitor) click to toggle source

def accept: (Visitor visitor) -> void

# File prism/node.rb, line 6042
def accept(visitor)
  visitor.visit_defined_node(self)
end

child_nodes() click to toggle source

def child_nodes: () -> Array[nil | Node]

# File prism/node.rb, line 6047
def child_nodes
  [value]
end

Also aliased as: deconstruct

comment_targets() click to toggle source

def comment_targets: () -> Array[Node | Location]

# File prism/node.rb, line 6057
def comment_targets
  [*lparen_loc, value, *rparen_loc, keyword_loc] #: Array[Prism::node | Location]
end

compact_child_nodes() click to toggle source

def compact_child_nodes: () -> Array

# File prism/node.rb, line 6052
def compact_child_nodes
  [value]
end

copy(lparen_loc: self.lparen_loc, value: self.value, rparen_loc: self.rparen_loc, keyword_loc: self.keyword_loc, location: self.location) click to toggle source

def copy: (?lparen_loc: Location?, ?value: Prism::node, ?rparen_loc: Location?, ?keyword_loc: Location, ?location: Location) -> DefinedNode

# File prism/node.rb, line 6062
def copy(lparen_loc: self.lparen_loc, value: self.value, rparen_loc: self.rparen_loc, keyword_loc: self.keyword_loc, location: self.location)
  DefinedNode.new(source, lparen_loc, value, rparen_loc, keyword_loc, location)
end

deconstruct()

def deconstruct: () -> Array[nil | Node]

Alias for: child_nodes

deconstruct_keys(keys) click to toggle source

def deconstruct_keys: (Array keys) -> { lparen_loc: Location?, value: Prism::node, rparen_loc: Location?, keyword_loc: Location, location: Location }

# File prism/node.rb, line 6070
def deconstruct_keys(keys)
  { lparen_loc: lparen_loc, value: value, rparen_loc: rparen_loc, keyword_loc: keyword_loc, location: location }
end

inspect() click to toggle source

def inspect -> String

# File prism/node.rb, line 6126
def inspect
  InspectVisitor.compose(self)
end

keyword() click to toggle source

def keyword: () -> String

# File prism/node.rb, line 6121
def keyword
  keyword_loc.slice
end

keyword_loc() click to toggle source

attr_reader keyword_loc: Location

# File prism/node.rb, line 6104
def keyword_loc
  location = @keyword_loc
  return location if location.is_a?(Location)
  @keyword_loc = Location.new(source, location >> 32, location & 0xFFFFFFFF)
end

lparen() click to toggle source

def lparen: () -> String?

# File prism/node.rb, line 6111
def lparen
  lparen_loc&.slice
end

lparen_loc() click to toggle source

attr_reader lparen_loc: Location?

# File prism/node.rb, line 6075
def lparen_loc
  location = @lparen_loc
  case location
  when nil
    nil
  when Location
    location
  else
    @lparen_loc = Location.new(source, location >> 32, location & 0xFFFFFFFF)
  end
end

rparen() click to toggle source

def rparen: () -> String?

# File prism/node.rb, line 6116
def rparen
  rparen_loc&.slice
end

rparen_loc() click to toggle source

attr_reader rparen_loc: Location?

# File prism/node.rb, line 6091
def rparen_loc
  location = @rparen_loc
  case location
  when nil
    nil
  when Location
    location
  else
    @rparen_loc = Location.new(source, location >> 32, location & 0xFFFFFFFF)
  end
end

type() click to toggle source

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 prism/node.rb, line 6144
def type
  :defined_node
end