> Non-static closures are turned into static ones if they are guaranteed not to make use of $this. > Stateless closures, i.e. those that are static, don't capt

> Non-static closures are turned into static ones if they are guaranteed not to make use of $this. > Stateless closures, i.e. those that are static, don't capture any variables and don't declare any static variables, are cached between uses.