class Prism::InNode
Represents the use of the ‘in` keyword in a case statement.
case a; in b then c end ^^^^^^^^^^^
Attributes
attr_reader pattern: Prism::node
attr_reader statements: StatementsNode
?
Public Class Methods
def initialize: (Prism::node pattern, StatementsNode
? statements, Location
in_loc
, Location
? then_loc
, Location
location) -> void
# File prism/node.rb, line 8958 def initialize(source, pattern, statements, in_loc, then_loc, location) @source = source @location = location @pattern = pattern @statements = statements @in_loc = in_loc @then_loc = then_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 prism/node.rb, line 9068 def self.type :in_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 prism/node.rb, line 9074 def ===(other) other.is_a?(InNode) && (pattern === other.pattern) && (statements === other.statements) && (in_loc.nil? == other.in_loc.nil?) && (then_loc.nil? == other.then_loc.nil?) end
def accept: (Visitor
visitor) -> void
# File prism/node.rb, line 8968 def accept(visitor) visitor.visit_in_node(self) end
def child_nodes
: () -> Array[nil | Node]
# File prism/node.rb, line 8973 def child_nodes [pattern, statements] end
def comment_targets
: () -> Array[Node | Location]
# File prism/node.rb, line 8986 def comment_targets [pattern, *statements, in_loc, *then_loc] #: Array[Prism::node | Location] end
def compact_child_nodes
: () -> Array
# File prism/node.rb, line 8978 def compact_child_nodes compact = [] #: Array[Prism::node] compact << pattern compact << statements if statements compact end
def copy: (?pattern: Prism::node, ?statements: StatementsNode
?, ?in_loc: Location
, ?then_loc: Location
?, ?location: Location
) -> InNode
# File prism/node.rb, line 8991 def copy(pattern: self.pattern, statements: self.statements, in_loc: self.in_loc, then_loc: self.then_loc, location: self.location) InNode.new(source, pattern, statements, in_loc, then_loc, location) end
def deconstruct_keys
: (Array keys) -> { pattern: Prism::node, statements: StatementsNode
?, in_loc
: Location
, then_loc
: Location
?, location: Location
}
# File prism/node.rb, line 8999 def deconstruct_keys(keys) { pattern: pattern, statements: statements, in_loc: in_loc, then_loc: then_loc, location: location } end
def in: () -> String
# File prism/node.rb, line 9030 def in in_loc.slice end
def inspect -> String
# File prism/node.rb, line 9040 def inspect InspectVisitor.compose(self) end
def then: () -> String?
# File prism/node.rb, line 9035 def then then_loc&.slice 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 prism/node.rb, line 9058 def type :in_node end