Class: Prism::UndefNode

Inherits:
PrismNode
  • Object
show all
Defined in:
lib/prism/node.rb,
ext/prism/api_node.c

Overview

Represents the use of the ‘undef` keyword.

undef :foo, :bar, :baz
^^^^^^^^^^^^^^^^^^^^^^

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(names, keyword_loc, location) ⇒ UndefNode

def initialize: (names: Array, keyword_loc: Location, location: Location) -> void



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# File 'lib/prism/node.rb', line 13686

def initialize(names, keyword_loc, location)
  @names = names
  @keyword_loc = keyword_loc
  @location = location
end

Instance Attribute Details

#keyword_locObject (readonly)

attr_reader keyword_loc: Location



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# File 'lib/prism/node.rb', line 13683

def keyword_loc
  @keyword_loc
end

#namesObject (readonly)

attr_reader names: Array



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# File 'lib/prism/node.rb', line 13680

def names
  @names
end

Instance Method Details

#accept(visitor) ⇒ Object

def accept: (visitor: Visitor) -> void



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# File 'lib/prism/node.rb', line 13693

def accept(visitor)
  visitor.visit_undef_node(self)
end

#child_nodesObject Also known as: deconstruct

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



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# File 'lib/prism/node.rb', line 13698

def child_nodes
  [*names]
end

#comment_targetsObject

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



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# File 'lib/prism/node.rb', line 13708

def comment_targets
  [*names, keyword_loc]
end

#compact_child_nodesObject

def compact_child_nodes: () -> Array



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# File 'lib/prism/node.rb', line 13703

def compact_child_nodes
  [*names]
end

#copy(**params) ⇒ Object

def copy: (**params) -> UndefNode



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# File 'lib/prism/node.rb', line 13713

def copy(**params)
  UndefNode.new(
    params.fetch(:names) { names },
    params.fetch(:keyword_loc) { keyword_loc },
    params.fetch(:location) { location },
  )
end

#deconstruct_keys(keys) ⇒ Object

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



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# File 'lib/prism/node.rb', line 13725

def deconstruct_keys(keys)
  { names: names, keyword_loc: keyword_loc, location: location }
end

#inspect(inspector = NodeInspector.new) ⇒ Object



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# File 'lib/prism/node.rb', line 13734

def inspect(inspector = NodeInspector.new)
  inspector << inspector.header(self)
  inspector << "├── names: #{inspector.list("#{inspector.prefix}│   ", names)}"
  inspector << "└── keyword_loc: #{inspector.location(keyword_loc)}\n"
  inspector.to_str
end

#keywordObject

def keyword: () -> String



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# File 'lib/prism/node.rb', line 13730

def keyword
  keyword_loc.slice
end

#typeObject

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



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# File 'lib/prism/node.rb', line 13755

def type
  :undef_node
end