# class Prism::DefNode

Represents a method definition.

    def method
    end
    ^^^^^^^^^^

### Attributes

body[R]

attr_reader body: `Node`?

def_keyword_loc[R]

attr_reader `def_keyword_loc`: `Location`

end_keyword_loc[R]

attr_reader `end_keyword_loc`: `Location`?

equal_loc[R]

attr_reader `equal_loc`: `Location`?

locals[R]

attr_reader locals: Array

locals_body_index[R]

attr_reader `locals_body_index`: `Integer`

lparen_loc[R]

attr_reader `lparen_loc`: `Location`?

name[R]

attr_reader name: `Symbol`

name_loc[R]

attr_reader `name_loc`: `Location`

operator_loc[R]

attr_reader `operator_loc`: `Location`?

parameters[R]

attr_reader parameters: `ParametersNode`?

receiver[R]

attr_reader receiver: `Node`?

rparen_loc[R]

attr_reader `rparen_loc`: `Location`?

### Public Class Methods

new(name, name_loc, receiver, parameters, body, locals, locals_body_index, def_keyword_loc, operator_loc, lparen_loc, rparen_loc, equal_loc, end_keyword_loc, location) click to toggle source

def initialize: (name: `Symbol`, `name_loc`: `Location`, receiver: `Node`?, parameters: `ParametersNode`?, body: `Node`?, locals: Array, `locals_body_index`: `Integer`, `def_keyword_loc`: `Location`, `operator_loc`: `Location`?, `lparen_loc`: `Location`?, `rparen_loc`: `Location`?, `equal_loc`: `Location`?, `end_keyword_loc`: `Location`?, location: `Location`) -> void

    # File lib/prism/node.rb, line 5278
    def initialize(name, name_loc, receiver, parameters, body, locals, locals_body_index, def_keyword_loc, operator_loc, lparen_loc, rparen_loc, equal_loc, end_keyword_loc, location)
      @name = name
      @name_loc = name_loc
      @receiver = receiver
      @parameters = parameters
      @body = body
      @locals = locals
      @locals_body_index = locals_body_index
      @def_keyword_loc = def_keyword_loc
      @operator_loc = operator_loc
      @lparen_loc = lparen_loc
      @rparen_loc = rparen_loc
      @equal_loc = equal_loc
      @end_keyword_loc = end_keyword_loc
      @location = location
    end

type() click to toggle source

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 5435
    def self.type
      :def_node
    end

### Public Instance Methods

accept(visitor) click to toggle source

def accept: (visitor: `Visitor`) -> void

    # File lib/prism/node.rb, line 5296
    def accept(visitor)
      visitor.visit_def_node(self)
    end

child_nodes() click to toggle source

def `child_nodes`: () -> Array[nil | Node]

    # File lib/prism/node.rb, line 5301
    def child_nodes
      [receiver, parameters, body]
    end

Also aliased as: deconstruct
comment_targets() click to toggle source

def `comment_targets`: () -> Array[Node | Location]

    # File lib/prism/node.rb, line 5315
    def comment_targets
      [name_loc, *receiver, *parameters, *body, def_keyword_loc, *operator_loc, *lparen_loc, *rparen_loc, *equal_loc, *end_keyword_loc]
    end

compact_child_nodes() click to toggle source

def `compact_child_nodes`: () -> Array

    # File lib/prism/node.rb, line 5306
    def compact_child_nodes
      compact = []
      compact << receiver if receiver
      compact << parameters if parameters
      compact << body if body
      compact
    end

copy(**params) click to toggle source

def copy: (**params) -> `DefNode`

    # File lib/prism/node.rb, line 5320
    def copy(**params)
      DefNode.new(
        params.fetch(:name) { name },
        params.fetch(:name_loc) { name_loc },
        params.fetch(:receiver) { receiver },
        params.fetch(:parameters) { parameters },
        params.fetch(:body) { body },
        params.fetch(:locals) { locals },
        params.fetch(:locals_body_index) { locals_body_index },
        params.fetch(:def_keyword_loc) { def_keyword_loc },
        params.fetch(:operator_loc) { operator_loc },
        params.fetch(:lparen_loc) { lparen_loc },
        params.fetch(:rparen_loc) { rparen_loc },
        params.fetch(:equal_loc) { equal_loc },
        params.fetch(:end_keyword_loc) { end_keyword_loc },
        params.fetch(:location) { location },
      )
    end

deconstruct()

def deconstruct: () -> Array[nil | Node]

Alias for: child_nodes
deconstruct_keys(keys) click to toggle source

def `deconstruct_keys`: (keys: Array) -> Hash[Symbol, nil | `Node` | Array | `String` | `Token` | Array | Location]

    # File lib/prism/node.rb, line 5343
    def deconstruct_keys(keys)
      { name: name, name_loc: name_loc, receiver: receiver, parameters: parameters, body: body, locals: locals, locals_body_index: locals_body_index, def_keyword_loc: def_keyword_loc, operator_loc: operator_loc, lparen_loc: lparen_loc, rparen_loc: rparen_loc, equal_loc: equal_loc, end_keyword_loc: end_keyword_loc, location: location }
    end

def_keyword() click to toggle source

def `def_keyword`: () -> `String`

    # File lib/prism/node.rb, line 5348
    def def_keyword
      def_keyword_loc.slice
    end

end_keyword() click to toggle source

def `end_keyword`: () -> `String`?

    # File lib/prism/node.rb, line 5373
    def end_keyword
      end_keyword_loc&.slice
    end

equal() click to toggle source

def equal: () -> `String`?

    # File lib/prism/node.rb, line 5368
    def equal
      equal_loc&.slice
    end

inspect(inspector = NodeInspector.new) click to toggle source

def inspect(inspector: NodeInspector) -> `String`

    # File lib/prism/node.rb, line 5378
    def inspect(inspector = NodeInspector.new)
      inspector << inspector.header(self)
      inspector << "├── name: #{name.inspect}\n"
      inspector << "├── name_loc: #{inspector.location(name_loc)}\n"
      if (receiver = self.receiver).nil?
        inspector << "├── receiver: ∅\n"
      else
        inspector << "├── receiver:\n"
        inspector << receiver.inspect(inspector.child_inspector("│   ")).delete_prefix(inspector.prefix)
      end
      if (parameters = self.parameters).nil?
        inspector << "├── parameters: ∅\n"
      else
        inspector << "├── parameters:\n"
        inspector << parameters.inspect(inspector.child_inspector("│   ")).delete_prefix(inspector.prefix)
      end
      if (body = self.body).nil?
        inspector << "├── body: ∅\n"
      else
        inspector << "├── body:\n"
        inspector << body.inspect(inspector.child_inspector("│   ")).delete_prefix(inspector.prefix)
      end
      inspector << "├── locals: #{locals.inspect}\n"
      inspector << "├── locals_body_index: #{locals_body_index.inspect}\n"
      inspector << "├── def_keyword_loc: #{inspector.location(def_keyword_loc)}\n"
      inspector << "├── operator_loc: #{inspector.location(operator_loc)}\n"
      inspector << "├── lparen_loc: #{inspector.location(lparen_loc)}\n"
      inspector << "├── rparen_loc: #{inspector.location(rparen_loc)}\n"
      inspector << "├── equal_loc: #{inspector.location(equal_loc)}\n"
      inspector << "└── end_keyword_loc: #{inspector.location(end_keyword_loc)}\n"
      inspector.to_str
    end

lparen() click to toggle source

def lparen: () -> `String`?

    # File lib/prism/node.rb, line 5358
    def lparen
      lparen_loc&.slice
    end

operator() click to toggle source

def operator: () -> `String`?

    # File lib/prism/node.rb, line 5353
    def operator
      operator_loc&.slice
    end

rparen() click to toggle source

def rparen: () -> `String`?

    # File lib/prism/node.rb, line 5363
    def rparen
      rparen_loc&.slice
    end

type() click to toggle source

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 5425
    def type
      :def_node
    end