class Prism::MultiTargetNode
Represents a multi-target expression.
a, (b, c) = 1, 2, 3 ^^^^^^
This can be a part of ‘MultiWriteNode` as above, or the target of a `for` loop
for a, b in [[1, 2], [3, 4]] ^^^^
Attributes
Represents the targets expressions before a splat node.
a, (b, c, *) = 1, 2, 3, 4, 5 ^^^^
The splat node can be absent, in that case all target expressions are in the left field.
a, (b, c) = 1, 2, 3, 4, 5 ^^^^
Represents a splat node in the target expression.
a, (b, *c) = 1, 2, 3, 4 ^^
The variable can be empty, this results in a ‘SplatNode` with a `nil` expression field.
a, (b, *) = 1, 2, 3, 4 ^
If the ‘*` is omitted, the field will containt an `ImplicitRestNode`
a, (b,) = 1, 2, 3, 4 ^
Represents the targets expressions after a splat node.
a, (*, b, c) = 1, 2, 3, 4, 5 ^^^^
Public Class Methods
def initialize: (Array[LocalVariableTargetNode | InstanceVariableTargetNode
| ClassVariableTargetNode
| GlobalVariableTargetNode
| ConstantTargetNode
| ConstantPathTargetNode
| CallTargetNode
| IndexTargetNode
| MultiTargetNode
| RequiredParameterNode
| BackReferenceReadNode
| NumberedReferenceReadNode] lefts, ImplicitRestNode
| SplatNode
| nil rest, Array[LocalVariableTargetNode | InstanceVariableTargetNode
| ClassVariableTargetNode
| GlobalVariableTargetNode
| ConstantTargetNode
| ConstantPathTargetNode
| CallTargetNode
| IndexTargetNode
| MultiTargetNode
| RequiredParameterNode
| BackReferenceReadNode] rights, Location
? lparen_loc
, Location
? rparen_loc
, Location
location) -> void
# File lib/prism/node.rb, line 13386 def initialize(source, lefts, rest, rights, lparen_loc, rparen_loc, location) @source = source @location = location @lefts = lefts @rest = rest @rights = rights @lparen_loc = lparen_loc @rparen_loc = rparen_loc 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 lib/prism/node.rb, line 13537 def self.type :multi_target_node end
Public Instance Methods
Implements case-equality for the node. This is effectively == but without comparing the value of locations. Locations are checked only for presence.
# File lib/prism/node.rb, line 13543 def ===(other) other.is_a?(MultiTargetNode) && (lefts.length == other.lefts.length) && lefts.zip(other.lefts).all? { |left, right| left === right } && (rest === other.rest) && (rights.length == other.rights.length) && rights.zip(other.rights).all? { |left, right| left === right } && (lparen_loc.nil? == other.lparen_loc.nil?) && (rparen_loc.nil? == other.rparen_loc.nil?) end
def accept: (Visitor
visitor) -> void
# File lib/prism/node.rb, line 13397 def accept(visitor) visitor.visit_multi_target_node(self) end
def child_nodes
: () -> Array[nil | Node]
# File lib/prism/node.rb, line 13402 def child_nodes [*lefts, rest, *rights] end
def comment_targets
: () -> Array[Node | Location]
# File lib/prism/node.rb, line 13416 def comment_targets [*lefts, *rest, *rights, *lparen_loc, *rparen_loc] #: Array[Prism::node | Location] end
def compact_child_nodes
: () -> Array
# File lib/prism/node.rb, line 13407 def compact_child_nodes compact = [] #: Array[Prism::node] compact.concat(lefts) compact << rest if rest compact.concat(rights) compact end
def copy: (?lefts: Array[LocalVariableTargetNode | InstanceVariableTargetNode
| ClassVariableTargetNode
| GlobalVariableTargetNode
| ConstantTargetNode
| ConstantPathTargetNode
| CallTargetNode
| IndexTargetNode
| MultiTargetNode
| RequiredParameterNode
| BackReferenceReadNode
| NumberedReferenceReadNode], ?rest: ImplicitRestNode
| SplatNode
| nil, ?rights: Array[LocalVariableTargetNode | InstanceVariableTargetNode
| ClassVariableTargetNode
| GlobalVariableTargetNode
| ConstantTargetNode
| ConstantPathTargetNode
| CallTargetNode
| IndexTargetNode
| MultiTargetNode
| RequiredParameterNode
| BackReferenceReadNode], ?lparen_loc: Location
?, ?rparen_loc: Location
?, ?location: Location
) -> MultiTargetNode
# File lib/prism/node.rb, line 13421 def copy(lefts: self.lefts, rest: self.rest, rights: self.rights, lparen_loc: self.lparen_loc, rparen_loc: self.rparen_loc, location: self.location) MultiTargetNode.new(source, lefts, rest, rights, lparen_loc, rparen_loc, location) end
def deconstruct_keys
: (Array keys) -> { lefts: Array[LocalVariableTargetNode | InstanceVariableTargetNode
| ClassVariableTargetNode
| GlobalVariableTargetNode
| ConstantTargetNode
| ConstantPathTargetNode
| CallTargetNode
| IndexTargetNode
| MultiTargetNode
| RequiredParameterNode
| BackReferenceReadNode
| NumberedReferenceReadNode], rest: ImplicitRestNode
| SplatNode
| nil, rights: Array[LocalVariableTargetNode | InstanceVariableTargetNode
| ClassVariableTargetNode
| GlobalVariableTargetNode
| ConstantTargetNode
| ConstantPathTargetNode
| CallTargetNode
| IndexTargetNode
| MultiTargetNode
| RequiredParameterNode
| BackReferenceReadNode], lparen_loc
: Location
?, rparen_loc
: Location
?, location: Location
}
# File lib/prism/node.rb, line 13429 def deconstruct_keys(keys) { lefts: lefts, rest: rest, rights: rights, lparen_loc: lparen_loc, rparen_loc: rparen_loc, location: location } end
def inspect -> String
# File lib/prism/node.rb, line 13509 def inspect InspectVisitor.compose(self) end
def lparen: () -> String
?
# File lib/prism/node.rb, line 13499 def lparen lparen_loc&.slice end
The location of the opening parenthesis.
a, (b, c) = 1, 2, 3 ^
# File lib/prism/node.rb, line 13470 def lparen_loc location = @lparen_loc case location when nil nil when Location location else @lparen_loc = Location.new(source, location >> 32, location & 0xFFFFFFFF) end end
def rparen: () -> String
?
# File lib/prism/node.rb, line 13504 def rparen rparen_loc&.slice end
The location of the closing parenthesis.
a, (b, c) = 1, 2, 3 ^
# File lib/prism/node.rb, line 13486 def rparen_loc location = @rparen_loc case location when nil nil when Location location else @rparen_loc = Location.new(source, location >> 32, location & 0xFFFFFFFF) end 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
# File lib/prism/node.rb, line 13527 def type :multi_target_node end