我试图打印出以下函数的参数:
pub async fn loop_until_hit_rate_limit<'a, T, Fut>(
object_arr: &'a [T],
settings: &'a Settings,
pool: &'a PgPool,
f: impl Fn(&'a Settings, &'a PgPool, &'a T) -> Fut + Copy,
rate_limit: usize,
) where
Fut: Future<Output = anyhow::Result<()>>,
{
// do stuff
println!("args were: {}, {}, {}, {}, {}", object_arr, settings, pool, f, rate_limit) // <--- how do I make this work?
}
天真的方法对于任何一个大括号都会失败,并给出以下错误信息:
^ `impl Fn(&'a Settings, &'a PgPool, &'a T) -> Fut + Copy` cannot be formatted with the default formatter
或者出现这个错误(对于 {:?}):
^ `impl Fn(&'a Settings, &'a PgPool, &'a T) -> Fut + Copy` cannot be formatted using `{:?}` because it doesn't implement `std::fmt::Debug`
这两种方法都是有道理的,但我不确定如何解决它们。我找到了这个线程,但它只打印调用函数的名称,并没有打印传入的函数。
有没有办法做到这一点?