Represents referencing an instance variable.
@foo ^^^^
The name of the instance variable, which is a ‘@` followed by an [identifier](github.com/ruby/prism/blob/main/docs/parsing_rules.md#identifiers).
@x # name `:@x` @_test # name `:@_test`
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 10196
def initialize(source, name, location)
@source = source
@location = location
@name = name
end
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 10271
def self.type
:instance_variable_read_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-3.4.0-preview1/lib/prism/node.rb, line 10277
def ===(other)
other.is_a?(InstanceVariableReadNode) &&
(name === other.name)
end
Implements case-equality for the node. This is effectively == but without comparing the value of locations. Locations are checked only for presence.
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 10203
def accept(visitor)
visitor.visit_instance_variable_read_node(self)
end
def accept: (Visitor
visitor) -> void
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 10208
def child_nodes
[]
end
def child_nodes
: () -> Array[nil | Node]
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 10218
def comment_targets
[] #: Array[Prism::node | Location]
end
def comment_targets
: () -> Array[Node | Location]
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 10213
def compact_child_nodes
[]
end
def compact_child_nodes
: () -> Array
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 10223
def copy(name: self.name, location: self.location)
InstanceVariableReadNode.new(source, name, location)
end
def copy: (?name: Symbol
, ?location: Location
) -> InstanceVariableReadNode
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 10231
def deconstruct_keys(keys)
{ name: name, location: location }
end
def deconstruct_keys
: (Array keys) -> { name: Symbol
, location: Location
}
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 10243
def inspect
InspectVisitor.compose(self)
end
def inspect -> String
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 10261
def type
:instance_variable_read_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