Struct Error

#[repr(transparent)]
pub struct Error {
    pub errno: i32,
}

错误码有两种使用场景:

1. 需要区分具体错误码: 比如底层target提供接口，需要调用者显示区分target
2. 无需区分具体错误码: 一般有高层次，粗粒度的容错处理机制，错误码用于日志输出. 对于后一种场景，调用者决定日志输出方式，因此接口的返回值也多使用Result<T, Error>. 这里就会存在Error具体取值的构造尽可能和Target无关，因此为此场景定义了几个常用业务下需要使用到的错误码:
3. Error::inval
4. Error::noent
5. Error::perm
6. Error::nomem
7. Error::busy
8. Error::timedout
9. Error::general 借用Target定义的错误码来表达业务层的常见错误. 因为此场景并不鼓励基于具体错误码进行容错处理，因此并不提供对应的is_***接口.

Fields

errno: i32

Implementations

impl Error

pub const fn new(errno: i32) -> Self

pub fn last() -> Self

pub const fn inval() -> Self

表示输入错误. 适用于业务层主动返回错误码，避免使用具体数字导致跨平台兼容问题.

pub const fn noent() -> Self

表示资源不存在. 适用于业务层主动返回错误码，避免使用具体数字导致跨平台兼容问题.

pub const fn perm() -> Self

表示权限不足. 适用于业务层主动返回错误码，避免使用具体数字导致跨平台兼容问题.

pub const fn nomem() -> Self

表示内存不足. 适用于业务层主动返回错误码，避免使用具体数字导致跨平台兼容问题.

pub const fn busy() -> Self

表示繁忙(内部资源受限)返回. 适用于业务层主动返回错误码，避免使用具体数字导致跨平台兼容问题.

pub const fn timedout() -> Self

表示超时返回. 适用于业务层主动返回错误码，避免使用具体数字导致跨平台兼容问题.

pub const fn general() -> Self

表示难以归类的通用错误. 适用于业务层主动返回错误码，避免使用具体数字导致跨平台兼容问题.

Trait Implementations

impl Clone for Error

fn clone(&self) -> Error

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Error

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for Error

fn default() -> Self

Returns the “default value” for a type.

impl Display for Error

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl From<Error> for Result<()>

fn from(err: Error) -> Self

Converts to this type from the input type.

impl From<i32> for Error

fn from(i32: i32) -> Self

Converts to this type from the input type.

impl Ord for Error

fn cmp(&self, other: &Error) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Error

fn eq(&self, other: &Error) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for Error

fn partial_cmp(&self, other: &Error) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Copy for Error

impl Eq for Error

impl StructuralPartialEq for Error