Class: Prism::HashPatternNode

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

Overview

Represents a hash pattern in pattern matching.

foo => { a: 1, b: 2 }
       ^^^^^^^^^^^^^^

foo => { a: 1, b: 2, **c }
       ^^^^^^^^^^^^^^^^^^^

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(constant, elements, rest, opening_loc, closing_loc, location) ⇒ HashPatternNode

def initialize: (constant: Node?, elements: Array, rest: Node?, opening_loc: Location?, closing_loc: Location?, location: Location) -> void



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# File 'lib/prism/node.rb', line 7593

def initialize(constant, elements, rest, opening_loc, closing_loc, location)
  @constant = constant
  @elements = elements
  @rest = rest
  @opening_loc = opening_loc
  @closing_loc = closing_loc
  @location = location
end

Instance Attribute Details

#closing_loc ⇒ Object (readonly)

attr_reader closing_loc: Location?



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# File 'lib/prism/node.rb', line 7590

def closing_loc
  @closing_loc
end

#constant ⇒ Object (readonly)

attr_reader constant: Node?



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# File 'lib/prism/node.rb', line 7578

def constant
  @constant
end

#elements ⇒ Object (readonly)

attr_reader elements: Array



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# File 'lib/prism/node.rb', line 7581

def elements
  @elements
end

#opening_loc ⇒ Object (readonly)

attr_reader opening_loc: Location?



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# File 'lib/prism/node.rb', line 7587

def opening_loc
  @opening_loc
end

#rest ⇒ Object (readonly)

attr_reader rest: Node?



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# File 'lib/prism/node.rb', line 7584

def rest
  @rest
end

Class Method Details

.type ⇒ Object

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



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# File 'lib/prism/node.rb', line 7701

def self.type
  :hash_pattern_node
end

Instance Method Details

#accept(visitor) ⇒ Object

def accept: (visitor: Visitor) -> void



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# File 'lib/prism/node.rb', line 7603

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

#child_nodes ⇒ Object Also known as: deconstruct

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



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# File 'lib/prism/node.rb', line 7608

def child_nodes
  [constant, *elements, rest]
end

#closing ⇒ Object

def closing: () -> String?



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# File 'lib/prism/node.rb', line 7652

def closing
  closing_loc&.slice
end

#comment_targets ⇒ Object

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



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# File 'lib/prism/node.rb', line 7622

def comment_targets
  [*constant, *elements, *rest, *opening_loc, *closing_loc]
end

#compact_child_nodes ⇒ Object

def compact_child_nodes: () -> Array



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# File 'lib/prism/node.rb', line 7613

def compact_child_nodes
  compact = []
  compact << constant if constant
  compact.concat(elements)
  compact << rest if rest
  compact
end

#copy(**params) ⇒ Object

def copy: (**params) -> HashPatternNode



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# File 'lib/prism/node.rb', line 7627

def copy(**params)
  HashPatternNode.new(
    params.fetch(:constant) { constant },
    params.fetch(:elements) { elements },
    params.fetch(:rest) { rest },
    params.fetch(:opening_loc) { opening_loc },
    params.fetch(:closing_loc) { closing_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 7642

def deconstruct_keys(keys)
  { constant: constant, elements: elements, rest: rest, opening_loc: opening_loc, closing_loc: closing_loc, location: location }
end

#inspect(inspector = NodeInspector.new) ⇒ Object

def inspect(inspector: NodeInspector) -> String



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# File 'lib/prism/node.rb', line 7657

def inspect(inspector = NodeInspector.new)
  inspector << inspector.header(self)
  if (constant = self.constant).nil?
    inspector << "├── constant: ∅\n"
  else
    inspector << "├── constant:\n"
    inspector << constant.inspect(inspector.child_inspector("│   ")).delete_prefix(inspector.prefix)
  end
  inspector << "├── elements: #{inspector.list("#{inspector.prefix}│   ", elements)}"
  if (rest = self.rest).nil?
    inspector << "├── rest: ∅\n"
  else
    inspector << "├── rest:\n"
    inspector << rest.inspect(inspector.child_inspector("│   ")).delete_prefix(inspector.prefix)
  end
  inspector << "├── opening_loc: #{inspector.location(opening_loc)}\n"
  inspector << "└── closing_loc: #{inspector.location(closing_loc)}\n"
  inspector.to_str
end

#opening ⇒ Object

def opening: () -> String?



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# File 'lib/prism/node.rb', line 7647

def opening
  opening_loc&.slice
end

#type ⇒ Object

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 7691

def type
  :hash_pattern_node
end