Represents assigning to a local variable in pattern matching.
foo => [bar => baz] ^^^^^^^^^^^^
attr_reader value: Prism::node
attr_reader target: Prism::node
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 3215
def initialize(source, value, target, operator_loc, location)
@source = source
@location = location
@value = value
@target = target
@operator_loc = operator_loc
end
def initialize: (Prism::node value, Prism::node target, Location
operator_loc
, Location
location) -> void
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 3303
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-3.4.0-preview1/lib/prism/node.rb, line 3309
def ===(other)
other.is_a?(CapturePatternNode) &&
(value === other.value) &&
(target === other.target) &&
(operator_loc.nil? == other.operator_loc.nil?)
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 3224
def accept(visitor)
visitor.visit_capture_pattern_node(self)
end
def accept: (Visitor
visitor) -> void
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 3229
def child_nodes
[value, target]
end
def child_nodes
: () -> Array[nil | Node]
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 3239
def comment_targets
[value, target, operator_loc] #: Array[Prism::node | Location]
end
def comment_targets
: () -> Array[Node | Location]
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 3234
def compact_child_nodes
[value, target]
end
def compact_child_nodes
: () -> Array
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 3244
def copy(value: self.value, target: self.target, operator_loc: self.operator_loc, location: self.location)
CapturePatternNode.new(source, value, target, operator_loc, location)
end
def copy: (?value: Prism::node, ?target: Prism::node, ?operator_loc: Location
, ?location: Location
) -> CapturePatternNode
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 3252
def deconstruct_keys(keys)
{ value: value, target: target, operator_loc: operator_loc, location: location }
end
def deconstruct_keys
: (Array keys) -> { value: Prism::node, target: Prism::node, operator_loc
: Location
, location: Location
}
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 3275
def inspect
InspectVisitor.compose(self)
end
def inspect -> String
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 3270
def operator
operator_loc.slice
end
def operator: () -> String
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 3263
def operator_loc
location = @operator_loc
return location if location.is_a?(Location)
@operator_loc = Location.new(source, location >> 32, location & 0xFFFFFFFF)
end
attr_reader operator_loc
: Location
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 3293
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