///
/// # Example
///
/// ```
/// # use anyhow::{bail, Result};
/// #
/// # fn has_permission(user: usize, resource: usize) -> bool {
/// #     true
/// # }
/// #
/// # fn main() -> Result<()> {
/// #     let user = 0;
/// #     let resource = 0;
/// #
/// if !has_permission(user, resource) {
///     bail!("permission denied for accessing {}", resource);
/// }
/// #     Ok(())
/// # }
/// ```
///
/// ```
/// # use anyhow::{bail, Result};
/// # use std::fmt::{self, Display};
/// #
/// # #[derive(Debug)]
/// # enum ScienceError {
/// #     RecursionLimitExceeded,
/// # }
/// #
/// # impl std::error::Error for ScienceError {}
/// #
/// # impl Display for ScienceError {
/// #     fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
/// #         unimplemented!()
/// #     }
/// # }
/// #
/// # const MAX_DEPTH: usize = 1;
/// #
/// # const IGNORE: &str = stringify! {
/// #[derive(Error, Debug)]
/// enum ScienceError {
///     #[error(display = "recursion limit exceeded")]
///     RecursionLimitExceeded,
///     ...
/// }
/// # };
///
/// # fn main() -> Result<()> {
/// #     let depth = 0;
/// #
/// if depth > MAX_DEPTH {
///     bail!(ScienceError::RecursionLimitExceeded);
/// }
/// #     Ok(())
/// # }
/// ```