The expression used as the condition of the `assert`

Property definitions

	# The expression used as the condition of the `assert`
	var n_expr: AExpr is writable, noinit

src/parser/parser_nodes.nit:2096,2--2097,38

	redef fun n_expr=(node)
	do
		_n_expr = node
		node.parent = self
	end

src/parser/parser_prod.nit:3550,2--3554,4