Represents the use of the ‘=>` operator.
foo => bar ^^^^^^^^^^
attr_reader value: Prism::node
attr_reader pattern: Prism::node
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 12858
def initialize(source, value, pattern, operator_loc, location)
@source = source
@location = location
@value = value
@pattern = pattern
@operator_loc = operator_loc
end
def initialize: (Prism::node value, Prism::node pattern, Location operator_loc, Location location) -> void
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 12946
def self.type
:match_required_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 12952
def ===(other)
other.is_a?(MatchRequiredNode) &&
(value === other.value) &&
(pattern === other.pattern) &&
(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 12867
def accept(visitor)
visitor.visit_match_required_node(self)
end
def accept: (Visitor visitor) -> void
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 12872
def child_nodes
[value, pattern]
end
def child_nodes: () -> Array[nil | Node]
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 12882
def comment_targets
[value, pattern, 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 12877
def compact_child_nodes
[value, pattern]
end
def compact_child_nodes: () -> Array
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 12887
def copy(value: self.value, pattern: self.pattern, operator_loc: self.operator_loc, location: self.location)
MatchRequiredNode.new(source, value, pattern, operator_loc, location)
end
def copy: (?value: Prism::node, ?pattern: Prism::node, ?operator_loc: Location, ?location: Location) -> MatchRequiredNode
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 12895
def deconstruct_keys(keys)
{ value: value, pattern: pattern, operator_loc: operator_loc, location: location }
end
def deconstruct_keys: (Array keys) -> { value: Prism::node, pattern: Prism::node, operator_loc: Location, location: Location }
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 12918
def inspect
InspectVisitor.compose(self)
end
def inspect -> String
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 12913
def operator
operator_loc.slice
end
def operator: () -> String
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 12906
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 12936
def type
:match_required_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