Struct EmptyStruct 

#[repr(C)]
pub struct EmptyStruct {
    pub _reserved: u8,
}

FFI-safe void type to replace () in Result types.

Since () (unit type) has zero size, it’s not FFI-safe. This type provides a minimal 1-byte representation that can be safely passed across the C ABI boundary.

Usage

Instead of Result<(), Error>, use Result<EmptyStruct, Error>.

Example

fn do_something() -> Result<EmptyStruct, MyError> {
    // ... do work ...
    Ok(EmptyStruct::default())
}

Fields

_reserved: u8

Reserved byte to ensure the struct has non-zero size. Always initialized to 0.

Implementations

impl EmptyStruct

pub const fn new() -> Self

Create a new EmptyStruct value (equivalent to ())

Trait Implementations

impl Clone for EmptyStruct

fn clone(&self) -> EmptyStruct

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for EmptyStruct

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

Formats the value using the given formatter.

impl Default for EmptyStruct

fn default() -> EmptyStruct

Returns the “default value” for a type.

impl From<()> for EmptyStruct

fn from(_: ()) -> Self

Converts to this type from the input type.

impl From<EmptyStruct> for ()

fn from(_: EmptyStruct) -> Self

Converts to this type from the input type.

impl Hash for EmptyStruct

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for EmptyStruct

fn cmp(&self, other: &EmptyStruct) -> 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 EmptyStruct

fn eq(&self, other: &EmptyStruct) -> 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 EmptyStruct

fn partial_cmp(&self, other: &EmptyStruct) -> 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 EmptyStruct

impl Eq for EmptyStruct

impl StructuralPartialEq for EmptyStruct