//! Miscellaneous utilities.

#[cold]
#[inline(always)]
fn cold() {}

/// A hint that `b` is likely to be true. See `core::intrinsics::likely`.
#[inline(always)]
pub fn likely(b: bool) -> bool {
    if !b {
        cold()
    }
    b
}

/// A hint that `b` is likely to be false. See `core::intrinsics::unlikely`.
#[inline(always)]
pub fn unlikely(b: bool) -> bool {
    if b {
        cold()
    }
    b
}

/// A version of `std::dbg` built on top of `log::debug` instead of
/// `std::eprintln`.
///
/// This code is copied from libstd, and inherits its copyright.
#[macro_export]
macro_rules! dbg {
    // NOTE: We cannot use `concat!` to make a static string as a format
    // argument of `log::debug!` because the `$expr` expression could be a
    // block (`{ .. }`), in which case the format string will be malformed.
    () => {
        log::debug!("")
    };
    ($expr:expr $(,)?) => {
        // Use of `match` here is intentional because it affects the lifetimes
        // of temporaries - https://stackoverflow.com/a/48732525/1063961
        match $expr {
            tmp => {
                log::debug!("{} = {:#?}", core::stringify!($expr), &tmp);
                tmp
            }
        }
    };
    ($($expr:expr),+ $(,)?) => {
        ($($crate::dbg!($expr)),+,)
    };
}