class Prism::BlockParametersNode
Represents a block’s parameters declaration.
-> (a, b = 1; local) { } ^^^^^^^^^^^^^^^^^ foo do |a, b = 1; local| ^^^^^^^^^^^^^^^^^ end
Attributes
attr_reader closing_loc
: Location
?
attr_reader locals: Array
attr_reader opening_loc
: Location
?
attr_reader parameters: ParametersNode
?
Public Class Methods
def initialize: (parameters: ParametersNode
?, locals: Array, opening_loc
: Location
?, closing_loc
: Location
?, location: Location
) -> void
# File prism/node.rb, line 1758 def initialize(parameters, locals, opening_loc, closing_loc, location) @parameters = parameters @locals = locals @opening_loc = opening_loc @closing_loc = closing_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 prism/node.rb, line 1857 def self.type :block_parameters_node end
Public Instance Methods
def accept: (visitor: Visitor
) -> void
# File prism/node.rb, line 1767 def accept(visitor) visitor.visit_block_parameters_node(self) end
def child_nodes
: () -> Array[nil | Node]
# File prism/node.rb, line 1772 def child_nodes [parameters, *locals] end
def closing: () -> String?
# File prism/node.rb, line 1814 def closing closing_loc&.slice end
def comment_targets
: () -> Array[Node | Location]
# File prism/node.rb, line 1785 def comment_targets [*parameters, *locals, *opening_loc, *closing_loc] end
def compact_child_nodes
: () -> Array
# File prism/node.rb, line 1777 def compact_child_nodes compact = [] compact << parameters if parameters compact.concat(locals) compact end
def copy: (**params) -> BlockParametersNode
# File prism/node.rb, line 1790 def copy(**params) BlockParametersNode.new( params.fetch(:parameters) { parameters }, params.fetch(:locals) { locals }, params.fetch(:opening_loc) { opening_loc }, params.fetch(:closing_loc) { closing_loc }, params.fetch(:location) { location }, ) end
def inspect(inspector: NodeInspector) -> String
# File prism/node.rb, line 1819 def inspect(inspector = NodeInspector.new) inspector << inspector.header(self) if (parameters = self.parameters).nil? inspector << "├── parameters: ∅\n" else inspector << "├── parameters:\n" inspector << parameters.inspect(inspector.child_inspector("│ ")).delete_prefix(inspector.prefix) end inspector << "├── locals: #{inspector.list("#{inspector.prefix}│ ", locals)}" inspector << "├── opening_loc: #{inspector.location(opening_loc)}\n" inspector << "└── closing_loc: #{inspector.location(closing_loc)}\n" inspector.to_str end
def opening: () -> String?
# File prism/node.rb, line 1809 def opening opening_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 1847 def type :block_parameters_node end