class Prism::AliasGlobalVariableNode

Represents the use of the ‘alias` keyword to alias a global variable.

alias $foo $bar
^^^^^^^^^^^^^^^

Attributes

new_name[R]

Represents the new name of the global variable that can be used after aliasing. This can be either a global variable, a back reference, or a numbered reference.

alias $foo $bar
      ^^^^

old_name[R]

Represents the old name of the global variable that could be used before aliasing. This can be either a global variable, a back reference, or a numbered reference.

alias $foo $bar
           ^^^^

Public Class Methods

new(source, new_name, old_name, keyword_loc, location) click to toggle source

def initialize: (Prism::node new_name, Prism::node old_name, Location keyword_loc, Location location) -> void

# File lib/prism/node.rb, line 144
def initialize(source, new_name, old_name, keyword_loc, location)
  @source = source
  @newline = false
  @location = location
  @new_name = new_name
  @old_name = old_name
  @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 lib/prism/node.rb, line 242
def self.type
  :alias_global_variable_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 lib/prism/node.rb, line 248
def ===(other)
  other.is_a?(AliasGlobalVariableNode) &&
    (new_name === other.new_name) &&
    (old_name === other.old_name) &&
    (keyword_loc.nil? == other.keyword_loc.nil?)
end

accept(visitor) click to toggle source

def accept: (Visitor visitor) -> void

# File lib/prism/node.rb, line 154
def accept(visitor)
  visitor.visit_alias_global_variable_node(self)
end

child_nodes() click to toggle source

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

# File lib/prism/node.rb, line 159
def child_nodes
  [new_name, old_name]
end

Also aliased as: deconstruct

comment_targets() click to toggle source

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

# File lib/prism/node.rb, line 169
def comment_targets
  [new_name, old_name, keyword_loc] #: Array[Prism::node | Location]
end

compact_child_nodes() click to toggle source

def compact_child_nodes: () -> Array

# File lib/prism/node.rb, line 164
def compact_child_nodes
  [new_name, old_name]
end

copy(new_name: self.new_name, old_name: self.old_name, keyword_loc: self.keyword_loc, location: self.location) click to toggle source

def copy: (?new_name: Prism::node, ?old_name: Prism::node, ?keyword_loc: Location, ?location: Location) -> AliasGlobalVariableNode

# File lib/prism/node.rb, line 174
def copy(new_name: self.new_name, old_name: self.old_name, keyword_loc: self.keyword_loc, location: self.location)
  AliasGlobalVariableNode.new(source, new_name, old_name, 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) -> { new_name: Prism::node, old_name: Prism::node, keyword_loc: Location, location: Location }

# File lib/prism/node.rb, line 182
def deconstruct_keys(keys)
  { new_name: new_name, old_name: old_name, keyword_loc: keyword_loc, location: location }
end

inspect() click to toggle source

def inspect -> String

# File lib/prism/node.rb, line 214
def inspect
  InspectVisitor.compose(self)
end

keyword() click to toggle source

def keyword: () -> String

# File lib/prism/node.rb, line 209
def keyword
  keyword_loc.slice
end

keyword_loc() click to toggle source

The location of the ‘alias` keyword.

alias $foo $bar
^^^^^

# File lib/prism/node.rb, line 202
def keyword_loc
  location = @keyword_loc
  return location if location.is_a?(Location)
  @keyword_loc = Location.new(source, location >> 32, location & 0xFFFFFFFF)
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 lib/prism/node.rb, line 232
def type
  :alias_global_variable_node
end