The top level node of any parse tree.
attr_reader statements: StatementsNode
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 15189
def initialize(source, locals, statements, location)
@source = source
@location = location
@locals = locals
@statements = statements
end
def initialize: (Array locals, StatementsNode statements, Location location) -> void
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 15264
def self.type
:program_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 15270
def ===(other)
other.is_a?(ProgramNode) &&
(locals.length == other.locals.length) &&
locals.zip(other.locals).all? { |left, right| left === right } &&
(statements === other.statements)
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 15197
def accept(visitor)
visitor.visit_program_node(self)
end
def accept: (Visitor visitor) -> void
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 15202
def child_nodes
[statements]
end
def child_nodes: () -> Array[nil | Node]
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 15212
def comment_targets
[statements] #: Array[Prism::node | Location]
end
def comment_targets: () -> Array[Node | Location]
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 15207
def compact_child_nodes
[statements]
end
def compact_child_nodes: () -> Array
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 15217
def copy(locals: self.locals, statements: self.statements, location: self.location)
ProgramNode.new(source, locals, statements, location)
end
def copy: (?locals: Array, ?statements: StatementsNode, ?location: Location) -> ProgramNode
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 15225
def deconstruct_keys(keys)
{ locals: locals, statements: statements, location: location }
end
def deconstruct_keys: (Array keys) -> { locals: Array, statements: StatementsNode, location: Location }
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 15236
def inspect
InspectVisitor.compose(self)
end
def inspect -> String
# File tmp/rubies/ruby-3.4.0-preview1/lib/prism/node.rb, line 15254
def type
:program_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