Class: Prism::GlobalVariableReadNode

Inherits:
PrismNode
  • Object
show all
Defined in:
lib/prism/node.rb,
ext/prism/api_node.c

Overview

Represents referencing a global variable.

$foo
^^^^

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(source, name, location) ⇒ GlobalVariableReadNode

def initialize: (Symbol name, Location location) -> void



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# File 'lib/prism/node.rb', line 7951

def initialize(source, name, location)
  @source = source
  @newline = false
  @location = location
  @name = name
end

Instance Attribute Details

#name ⇒ Object (readonly)

The name of the global variable, which is a ‘$` followed by an [identifier](github.com/ruby/prism/blob/main/docs/parsing_rules.md#identifier). Alternatively, it can be one of the special global variables designated by a symbol.

$foo   # name `:$foo`

$_Test # name `:$_Test`



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# File 'lib/prism/node.rb', line 7996

def name
  @name
end

Class Method Details

.type ⇒ Object

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



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# File 'lib/prism/node.rb', line 8027

def self.type
  :global_variable_read_node
end

Instance Method Details

#===(other) ⇒ Object

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



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# File 'lib/prism/node.rb', line 8033

def ===(other)
  other.is_a?(GlobalVariableReadNode) &&
    (name === other.name)
end

#accept(visitor) ⇒ Object

def accept: (Visitor visitor) -> void



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# File 'lib/prism/node.rb', line 7959

def accept(visitor)
  visitor.visit_global_variable_read_node(self)
end

#child_nodes ⇒ Object Also known as: deconstruct

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



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# File 'lib/prism/node.rb', line 7964

def child_nodes
  []
end

#comment_targets ⇒ Object

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



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# File 'lib/prism/node.rb', line 7974

def comment_targets
  [] #: Array[Prism::node | Location]
end

#compact_child_nodes ⇒ Object

def compact_child_nodes: () -> Array



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# File 'lib/prism/node.rb', line 7969

def compact_child_nodes
  []
end

#copy(name: self.name, location: self.location) ⇒ Object

def copy: (?name: Symbol, ?location: Location) -> GlobalVariableReadNode



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# File 'lib/prism/node.rb', line 7979

def copy(name: self.name, location: self.location)
  GlobalVariableReadNode.new(source, name, location)
end

#deconstruct_keys(keys) ⇒ Object

def deconstruct_keys: (Array keys) -> { name: Symbol, location: Location }



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# File 'lib/prism/node.rb', line 7987

def deconstruct_keys(keys)
  { name: name, location: location }
end

#inspect ⇒ Object

def inspect -> String



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# File 'lib/prism/node.rb', line 7999

def inspect
  InspectVisitor.compose(self)
end

#type ⇒ Object

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



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# File 'lib/prism/node.rb', line 8017

def type
  :global_variable_read_node
end