class Prism::ElseNode
Represents an ‘else` clause in a `case`, `if`, or `unless` statement.
if a then b else c end ^^^^^^^^^^
Attributes
attr_reader statements: StatementsNode
?
Public Class Methods
def initialize: (Location
else_keyword_loc
, StatementsNode
? statements, Location
? end_keyword_loc
, Location
location) -> void
# File prism/node.rb, line 6175 def initialize(source, else_keyword_loc, statements, end_keyword_loc, location) @source = source @location = location @else_keyword_loc = else_keyword_loc @statements = statements @end_keyword_loc = end_keyword_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 6280 def self.type :else_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 6286 def ===(other) other.is_a?(ElseNode) && (else_keyword_loc.nil? == other.else_keyword_loc.nil?) && (statements === other.statements) && (end_keyword_loc.nil? == other.end_keyword_loc.nil?) end
def accept: (Visitor
visitor) -> void
# File prism/node.rb, line 6184 def accept(visitor) visitor.visit_else_node(self) end
def child_nodes
: () -> Array[nil | Node]
# File prism/node.rb, line 6189 def child_nodes [statements] end
def comment_targets
: () -> Array[Node | Location]
# File prism/node.rb, line 6201 def comment_targets [else_keyword_loc, *statements, *end_keyword_loc] #: Array[Prism::node | Location] end
def compact_child_nodes
: () -> Array
# File prism/node.rb, line 6194 def compact_child_nodes compact = [] #: Array[Prism::node] compact << statements if statements compact end
def copy: (?else_keyword_loc: Location
, ?statements: StatementsNode
?, ?end_keyword_loc: Location
?, ?location: Location
) -> ElseNode
# File prism/node.rb, line 6206 def copy(else_keyword_loc: self.else_keyword_loc, statements: self.statements, end_keyword_loc: self.end_keyword_loc, location: self.location) ElseNode.new(source, else_keyword_loc, statements, end_keyword_loc, location) end
def deconstruct_keys
: (Array keys) -> { else_keyword_loc
: Location
, statements: StatementsNode
?, end_keyword_loc
: Location
?, location: Location
}
# File prism/node.rb, line 6214 def deconstruct_keys(keys) { else_keyword_loc: else_keyword_loc, statements: statements, end_keyword_loc: end_keyword_loc, location: location } end
def else_keyword
: () -> String
# File prism/node.rb, line 6242 def else_keyword else_keyword_loc.slice end
attr_reader else_keyword_loc
: Location
# File prism/node.rb, line 6219 def else_keyword_loc location = @else_keyword_loc return location if location.is_a?(Location) @else_keyword_loc = Location.new(source, location >> 32, location & 0xFFFFFFFF) end
def end_keyword
: () -> String?
# File prism/node.rb, line 6247 def end_keyword end_keyword_loc&.slice end
attr_reader end_keyword_loc
: Location
?
# File prism/node.rb, line 6229 def end_keyword_loc location = @end_keyword_loc case location when nil nil when Location location else @end_keyword_loc = Location.new(source, location >> 32, location & 0xFFFFFFFF) end end
def inspect -> String
# File prism/node.rb, line 6252 def inspect InspectVisitor.compose(self) 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 6270 def type :else_node end