Class: Prism::WhenNode

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

Overview

Represents the use of the ‘when` keyword within a case statement.

case true
when true
^^^^^^^^^
end

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(keyword_loc, conditions, statements, location) ⇒ WhenNode

def initialize: (keyword_loc: Location, conditions: Array, statements: StatementsNode?, location: Location) -> void



14039
14040
14041
14042
14043
14044
 
# File 'lib/prism/node.rb', line 14039

def initialize(keyword_loc, conditions, statements, location)
  @keyword_loc = keyword_loc
  @conditions = conditions
  @statements = statements
  @location = location
end

Instance Attribute Details

#conditions ⇒ Object (readonly)

attr_reader conditions: Array



14033
14034
14035
 
# File 'lib/prism/node.rb', line 14033

def conditions
  @conditions
end

#keyword_loc ⇒ Object (readonly)

attr_reader keyword_loc: Location



14030
14031
14032
 
# File 'lib/prism/node.rb', line 14030

def keyword_loc
  @keyword_loc
end

#statements ⇒ Object (readonly)

attr_reader statements: StatementsNode?



14036
14037
14038
 
# File 'lib/prism/node.rb', line 14036

def statements
  @statements
end

Instance Method Details

#accept(visitor) ⇒ Object

def accept: (visitor: Visitor) -> void



14047
14048
14049
 
# File 'lib/prism/node.rb', line 14047

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

#child_nodes ⇒ Object Also known as: deconstruct

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



14052
14053
14054
 
# File 'lib/prism/node.rb', line 14052

def child_nodes
  [*conditions, statements]
end

#comment_targets ⇒ Object

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



14065
14066
14067
 
# File 'lib/prism/node.rb', line 14065

def comment_targets
  [keyword_loc, *conditions, *statements]
end

#compact_child_nodes ⇒ Object

def compact_child_nodes: () -> Array



14057
14058
14059
14060
14061
14062
 
# File 'lib/prism/node.rb', line 14057

def compact_child_nodes
  compact = []
  compact.concat(conditions)
  compact << statements if statements
  compact
end

#copy(**params) ⇒ Object

def copy: (**params) -> WhenNode



14070
14071
14072
14073
14074
14075
14076
14077
 
# File 'lib/prism/node.rb', line 14070

def copy(**params)
  WhenNode.new(
    params.fetch(:keyword_loc) { keyword_loc },
    params.fetch(:conditions) { conditions },
    params.fetch(:statements) { statements },
    params.fetch(:location) { location },
  )
end

#deconstruct_keys(keys) ⇒ Object

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



14083
14084
14085
 
# File 'lib/prism/node.rb', line 14083

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

#inspect(inspector = NodeInspector.new) ⇒ Object 



14092
14093
14094
14095
14096
14097
14098
14099
14100
14101
14102
14103
 
# File 'lib/prism/node.rb', line 14092

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

#keyword ⇒ Object

def keyword: () -> String



14088
14089
14090
 
# File 'lib/prism/node.rb', line 14088

def keyword
  keyword_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



14119
14120
14121
 
# File 'lib/prism/node.rb', line 14119

def type
  :when_node
end