private class SimpleMiscVisitor
	super Visitor
	redef fun visit(n)
	do
		n.accept_simple_misc(self)
	end

	# Number of nested once
	var once_count: Int = 0

	var toolcontext: ToolContext

	fun warning(node: ANode, tag, msg: String)
	do
		toolcontext.warning(node.hot_location, tag, msg)
	end

	# Issue a warning if `sub` is a standalone `do` block.
	fun check_do_expr(sub: nullable AExpr)
	do
		if sub isa ADoExpr then
			warning(sub, "useless-do", "Warning: superfluous `do` block.")
		end
	end
end