class Prism::ElseNode
Represents an ‘else` clause in a `case`, `if`, or `unless` statement.
if a then b else c end ^^^^^^^^^^
Attributes
attr_reader else_keyword_loc
: Location
attr_reader end_keyword_loc
: Location
?
attr_reader statements: StatementsNode
?
Public Class Methods
def initialize: (else_keyword_loc
: Location
, statements: StatementsNode
?, end_keyword_loc
: Location
?, location: Location
) -> void
# File lib/prism/node.rb, line 5575 def initialize(else_keyword_loc, statements, end_keyword_loc, location) @else_keyword_loc = else_keyword_loc @statements = statements @end_keyword_loc = end_keyword_loc @location = location 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 5670 def self.type :else_node end
Public Instance Methods
def accept: (visitor: Visitor
) -> void
# File lib/prism/node.rb, line 5583 def accept(visitor) visitor.visit_else_node(self) end
def child_nodes
: () -> Array[nil | Node]
# File lib/prism/node.rb, line 5588 def child_nodes [statements] end
def comment_targets
: () -> Array[Node | Location]
# File lib/prism/node.rb, line 5600 def comment_targets [else_keyword_loc, *statements, *end_keyword_loc] end
def compact_child_nodes
: () -> Array
# File lib/prism/node.rb, line 5593 def compact_child_nodes compact = [] compact << statements if statements compact end
def copy: (**params) -> ElseNode
# File lib/prism/node.rb, line 5605 def copy(**params) ElseNode.new( params.fetch(:else_keyword_loc) { else_keyword_loc }, params.fetch(:statements) { statements }, params.fetch(:end_keyword_loc) { end_keyword_loc }, params.fetch(:location) { location }, ) end
def else_keyword
: () -> String
# File lib/prism/node.rb, line 5623 def else_keyword else_keyword_loc.slice end
def end_keyword
: () -> String
?
# File lib/prism/node.rb, line 5628 def end_keyword end_keyword_loc&.slice end
def inspect(inspector: NodeInspector) -> String
# File lib/prism/node.rb, line 5633 def inspect(inspector = NodeInspector.new) inspector << inspector.header(self) inspector << "├── else_keyword_loc: #{inspector.location(else_keyword_loc)}\n" if (statements = self.statements).nil? inspector << "├── statements: ∅\n" else inspector << "├── statements:\n" inspector << statements.inspect(inspector.child_inspector("│ ")).delete_prefix(inspector.prefix) end inspector << "└── end_keyword_loc: #{inspector.location(end_keyword_loc)}\n" inspector.to_str 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 5660 def type :else_node end