Represents a hash pattern in pattern matching.
foo => { a: 1, b: 2 }
^^^^^^^^^^^^^^
foo => { a: 1, b: 2, **c }
^^^^^^^^^^^^^^^^^^^
attr_reader constant: Prism::node?
attr_reader rest: AssocSplatNode | NoKeywordsParameterNode | nil
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 8322
def initialize(source, constant, elements, rest, opening_loc, closing_loc, location)
@source = source
@location = location
@constant = constant
@elements = elements
@rest = rest
@opening_loc = opening_loc
@closing_loc = closing_loc
end
def initialize: (Prism::node? constant, Array elements, AssocSplatNode | NoKeywordsParameterNode | nil rest, Location? opening_loc, Location? closing_loc, Location location) -> void
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 8443
def self.type
:hash_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 8449
def ===(other)
other.is_a?(HashPatternNode) &&
(constant === other.constant) &&
(elements.length == other.elements.length) &&
elements.zip(other.elements).all? { |left, right| left === right } &&
(rest === other.rest) &&
(opening_loc.nil? == other.opening_loc.nil?) &&
(closing_loc.nil? == other.closing_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 8333
def accept(visitor)
visitor.visit_hash_pattern_node(self)
end
def accept: (Visitor visitor) -> void
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 8338
def child_nodes
[constant, *elements, rest]
end
def child_nodes: () -> Array[nil | Node]
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 8410
def closing
closing_loc&.slice
end
def closing: () -> String?
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 8392
def closing_loc
location = @closing_loc
case location
when nil
nil
when Location
location
else
@closing_loc = Location.new(source, location >> 32, location & 0xFFFFFFFF)
end
end
attr_reader closing_loc: Location?
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 8352
def comment_targets
[*constant, *elements, *rest, *opening_loc, *closing_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 8343
def compact_child_nodes
compact = [] #: Array[Prism::node]
compact << constant if constant
compact.concat(elements)
compact << rest if rest
compact
end
def compact_child_nodes: () -> Array
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 8357
def copy(constant: self.constant, elements: self.elements, rest: self.rest, opening_loc: self.opening_loc, closing_loc: self.closing_loc, location: self.location)
HashPatternNode.new(source, constant, elements, rest, opening_loc, closing_loc, location)
end
def copy: (?constant: Prism::node?, ?elements: Array, ?rest: AssocSplatNode | NoKeywordsParameterNode | nil, ?opening_loc: Location?, ?closing_loc: Location?, ?location: Location) -> HashPatternNode
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 8365
def deconstruct_keys(keys)
{ constant: constant, elements: elements, rest: rest, opening_loc: opening_loc, closing_loc: closing_loc, location: location }
end
def deconstruct_keys: (Array keys) -> { constant: Prism::node?, elements: Array, rest: AssocSplatNode | NoKeywordsParameterNode | nil, opening_loc: Location?, closing_loc: Location?, location: Location }
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 8415
def inspect
InspectVisitor.compose(self)
end
def inspect -> String
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 8405
def opening
opening_loc&.slice
end
def opening: () -> String?
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 8379
def opening_loc
location = @opening_loc
case location
when nil
nil
when Location
location
else
@opening_loc = Location.new(source, location >> 32, location & 0xFFFFFFFF)
end
end
attr_reader opening_loc: Location?
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 8433
def type
:hash_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