//! Error types live here.
-use std::str::FromStr;
-use std::ffi::c_void;
+use alloc::str::FromStr;
+use core::ffi::c_void;
use core::convert::Infallible;
use bitcoin::hashes::Hash;
use crate::c_types::*;
+#[cfg(feature="no-std")]
+use alloc::{vec::Vec, boxed::Box};
/// Indicates an error on the client's part (usually some variant of attempting to use too-low or
/// too-high values)