fncache 0.1.2

A zero-boilerplate Rust library for function-level caching with pluggable backends
Documentation 
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//! Error types for the fncache library.

use serde::{Deserialize, Serialize};
use std::fmt;

/// The main error type for the fncache library.
#[derive(Debug, thiserror::Error, PartialEq, Serialize, Deserialize)]
pub enum Error {
    /// An error that occurred during serialization or deserialization.
    #[error("Codec error: {0}")]
    Codec(String),

    /// The requested key was not found in the cache.
    #[error("Cache miss for key")]
    CacheMiss,

    /// The backend returned an error.
    #[error("Backend error: {0}")]
    Backend(String),

    /// An error that occurred while initializing the global cache more than once.
    #[error("global cache has already been initialized")]
    AlreadyInitialized,

    /// The requested feature is not implemented.
    #[error("Feature not implemented: {0}")]
    NotImplemented(String),

    /// An error occurred when acquiring a lock.
    #[error("Failed to acquire lock")]
    LockError,

    /// The requested key was not found in the registered warmers.
    #[error("Key not found in registered warmers")]
    KeyNotFound,

    /// An error that doesn't fit into other categories.
    #[error("Cache error: {0}")]
    Other(String),
}

impl Error {
    /// Creates a new backend error.
    pub fn backend<E: fmt::Display>(error: E) -> Self {
        Self::Backend(error.to_string())
    }

    /// Creates a new other error.
    pub fn other<E: fmt::Display>(error: E) -> Self {
        Self::Other(error.to_string())
    }
}

/// A specialized `Result` type for cache operations.
pub type Result<T> = std::result::Result<T, Error>;

/// Implement From<std::io::Error> for Error to allow the use of ? with I/O operations
impl From<std::io::Error> for Error {
    fn from(error: std::io::Error) -> Self {
        Error::Backend(format!("I/O error: {}", error))
    }
}