Struct static_reflect::builtins::AsmOption

#[repr(C)]
pub struct AsmOption<T> { /* fields omitted */ }

A FFI-safe alternative to Rust’s std::option::Option.

Unlike the Rust type, this does not use the null-pointer optimization.

NOTE: This type doesn’t implement Drop.

Safety

This type does not enforce its safety variants, just like AsmSlice. However, the first field must be a valid bool.

A valid type can only be in one of two states:

1. {present: false, value: undefined}
2. {present: false, value: any}

Implementations

impl AsmOption<()>

pub const fn present_field_offset() -> usize

The offset of the ‘present’ field

This should be zero, regardless of the inner type

pub const fn value_field_offset(element_type: &TypeInfo<'_>) -> usize

The offset of the value field

This should be equal to the type’s alignment

impl<T> AsmOption<T>

pub fn none() -> AsmOption<T>

An option with no value

pub fn some(value: T) -> AsmOption<T>

Create an option with a value

pub unsafe fn assume_valid(self) -> Option<T>

Assume that this option is valid

This type is often used to ferry things across FFI boundaries, so it’s the callers repsonsibility to be safe with it.

Safety

The caller assumes that the underlying memory is valid. If not, undefined behavior will result.

pub fn is_present(&self) -> bool

If the value of the option is present.

Trait Implementations

impl<T: Debug> Debug for AsmOption<T>

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

Formats the value using the given formatter.

impl<T> From<Option<T>> for AsmOption<T>

fn from(o: Option<T>) -> AsmOption<T>

Performs the conversion.

impl<T: StaticReflect> StaticReflect for AsmOption<T>

const TYPE_INFO: TypeInfo<'static>

The static information about the type’s representation

impl<T: Send> Send for AsmOption<T>

This is an owned value, so it’s safe to send