Property definitions

nitc $ AExternClasskind :: defaultinit
# An extern class modifier (`extern class`)
class AExternClasskind
	super AClasskind

	# The `extern` keyword.
	var n_kwextern: TKwextern is writable, noinit

	# The `class` keyword.
	var n_kwclass: nullable TKwclass = null is writable
end
src/parser/parser_nodes.nit:1330,1--1339,3