Class: Code::Node::While

Inherits:
Code::Node show all
Defined in:
lib/code/node/while.rb

Constant Summary collapse

WHILE_KEYWORD = 
"while"
UNTIL_KEYWORD = 
"until"
LOOP_KEYWORD = 
"loop"

Instance Method Summary collapse

Methods inherited from Code::Node

#resolve

Constructor Details

#initialize(parsed) ⇒ While

Returns a new instance of While.



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# File 'lib/code/node/while.rb', line 10

def initialize(parsed)
  @operator = parsed.delete(:operator)
  @statement = Statement.new(parsed.delete(:statement)) if parsed[:statement]
  @body = Code.new(parsed.delete(:body))
  super(parsed)
end

Instance Method Details

#evaluate(**args) ⇒ Object 



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# File 'lib/code/node/while.rb', line 17

def evaluate(**args)
  case @operator
  when WHILE_KEYWORD
    last = Object::Nothing.new

    last = @body.evaluate(**args) while @statement.evaluate(
      **args
    ).truthy?

    last
  when UNTIL_KEYWORD
    last = Object::Nothing.new

    last = @body.evaluate(**args) while @statement.evaluate(**args).falsy?

    last
  when LOOP_KEYWORD
    loop { @body.evaluate(**args) }
    raise NotImplementedError
  else
    raise NotImplementedError, @operator
  end
rescue Error::Break => e
  e.value || Object::Nothing.new
end