Represents assigning to a local variable in pattern matching.
foo => [bar => baz]
^^^^^^^^^^^^
attr_reader operator_loc: Location
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 2835
def initialize(value, target, operator_loc, location)
@value = value
@target = target
@operator_loc = operator_loc
@location = location
end
def initialize: (value: Node, target: Node, operator_loc: Location, location: Location) -> void
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 2920
def self.type
:capture_pattern_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 2843
def accept(visitor)
visitor.visit_capture_pattern_node(self)
end
def accept: (visitor: Visitor) -> void
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 2848
def child_nodes
[value, target]
end
def child_nodes: () -> Array[nil | Node]
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 2858
def comment_targets
[value, target, operator_loc]
end
def comment_targets: () -> Array[Node | Location]
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 2853
def compact_child_nodes
[value, target]
end
def compact_child_nodes: () -> Array
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 2863
def copy(**params)
CapturePatternNode.new(
params.fetch(:value) { value },
params.fetch(:target) { target },
params.fetch(:operator_loc) { operator_loc },
params.fetch(:location) { location },
)
end
def copy: (**params) -> CapturePatternNode
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 2876
def deconstruct_keys(keys)
{ value: value, target: target, operator_loc: operator_loc, location: location }
end
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 2886
def inspect(inspector = NodeInspector.new)
inspector << inspector.header(self)
inspector << "├── value:\n"
inspector << inspector.child_node(value, "│ ")
inspector << "├── target:\n"
inspector << inspector.child_node(target, "│ ")
inspector << "└── operator_loc: #{inspector.location(operator_loc)}\n"
inspector.to_str
end
def inspect(inspector: NodeInspector) -> String
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 2881
def operator
operator_loc.slice
end
def operator: () -> String
# File tmp/rubies/ruby-3.3.0/lib/prism/node.rb, line 2910
def type
:capture_pattern_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