ENV.key?(name) â true or false Class Public methods Returns true

ENV.index(value) â key Class Public methods Deprecated method that is equivalent

ENV.store(name, value) â value Class Public methods Sets the environment variable

ENV.each_key { |name| } â HashENV.each_key â Enumerator Class Public methods

ENV.reject! { |name, value| } â ENV or nilENV.reject! â Enumerator Class Public methods

ENV.values_at(name, ...) â Array Class Public methods Returns an array containing

ENV.reject { |name, value| } â HashENV.reject â Enumerator Class Public methods

ENV.length Class Public methods Returns the number of environment variables

ENV.has_value?(value) â true or false Class Public methods Returns true

ENV.to_s â "ENV" Class Public methods Returns âENVâ