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/// Gets the value in the `Some` variant.
///
/// # Panics
///
/// Panics if `$opt` is a None.
///
/// # Example
///
/// ```rust
/// use const_panic::unwrap_some;
///
/// const SUM: u8 = unwrap_some!(add_up(&[3, 5, 8, 13]));
///
/// assert_eq!(SUM, 29);
///
///
/// const fn add_up(mut slice: &[u8]) -> Option<u8> {
/// let mut sum = 0u8;
///
/// while let [x, ref rem @ ..] = *slice {
/// match sum.checked_add(x) {
/// Some(x) => sum = x,
/// None => return None,
/// }
/// slice = rem;
/// }
///
/// Some(sum)
/// }
///
/// ```
///
///
/// ### Error
///
/// This is what the compile-time error looks like when attempting to unwrap a `None`:
///
/// ```text
/// error[E0080]: evaluation of constant value failed
/// --> src/macros/unwrapping.rs:10:17
/// |
/// 6 | const SUM: u8 = unwrap_some!(add_up(&[3, 5, 8, 13, 250]));
/// | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the evaluated program panicked at '
/// invoked `unwrap_some` macro with a `None` value', src/macros/unwrapping.rs:6:17
/// |
/// = note: this error originates in the macro `unwrap_some` (in Nightly builds, run with -Z macro-backtrace for more info)
///
/// ```
///
/// Gets the value in the `Ok` variant.
///
/// # Panics
///
/// This panics if `$res` is an `Err`, including the debug-formatted error in the panic message.
///
/// # Example
///
/// The struct formatting below requires the `"non_basic"` feature (enabled by default)
///
/// use const_panic::unwrap_ok;
///
/// const SUM: u64 = unwrap_ok!(add_up_evens(&[2, 4, 8, 16]));
///
/// assert_eq!(SUM, 30);
///
/// const fn add_up_evens(slice: &[u8]) -> Result<u64, OddError> {
/// let mut sum = 0u64;
/// let mut i = 0;
///
/// while i < slice.len() {
/// let x = slice[i];
///
/// if x % 2 == 1 {
/// return Err(OddError{at: i, number: x});
/// }
///
/// sum += x as u64;
/// i += 1;
/// }
///
/// Ok(sum)
/// }
///
///
/// struct OddError {
/// at: usize,
/// number: u8,
/// }
///
/// // You can also use `#[derive(PanicFmt))]` with the "derive" feature
/// const_panic::impl_panicfmt!{
/// struct OddError {
/// at: usize,
/// number: u8,
/// }
/// }
///
/// ```
///
/// ### Error
///
/// This is what the compile-time error looks like when attempting to unwrap an `Err`:
///
/// ```text
/// error[E0080]: evaluation of constant value failed
/// --> src/macros/unwrapping.rs:51:18
/// |
/// 6 | const SUM: u64 = unwrap_ok!(add_up_evens(&[3, 5, 8, 13]));
/// | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the evaluated program panicked at '
/// invoked `unwrap_ok` macro with an `Err` value: OddError { at: 0, number: 3 }', src/macros/unwrapping.rs:6:18
/// |
/// ```
/// Gets the value in the `Err` variant.
///
/// # Panics
///
/// This panics if `$res` is an `Ok`, including the debug-formatted value in the panic message.
///
/// # Example
///
/// ```rust
/// use const_panic::unwrap_err;
///
/// type Res = Result<u32, &'static str>;
///
/// const ERR: &str = unwrap_err!(Res::Err("this is an error"));
///
/// assert_eq!(ERR, "this is an error");
///
/// ```
///
/// ### Error
///
/// This is what the compile-time error looks like when attempting to unwrap an `Ok`:
///
/// ```text
/// error[E0080]: evaluation of constant value failed
/// --> src/macros/unwrapping.rs:174:19
/// |
/// 8 | const ERR: &str = unwrap_err!(Res::Ok(1234));
/// | ^^^^^^^^^^^^^^^^^^^^^^^^^^ the evaluated program panicked at '
/// invoked `unwrap_err` macro with an `Ok` value: 1234', src/macros/unwrapping.rs:8:19
/// |
/// ```