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pub struct StaticInitializedOnce<Value: Sized>
{
#[cfg(debug_assertions)] initialization_pattern: u8,
value: MaybeUninit<Value>,
}
impl<Value: Sized> StaticInitializedOnce<Value>
{
#[cfg(debug_assertions)] const Uninitialized: u8 = 0x00;
#[cfg(debug_assertions)] const Initialized: u8 = 0xFF;
#[inline(always)]
pub const fn uninitialized() -> Self
{
Self
{
#[cfg(debug_assertions)] initialization_pattern: Self::Uninitialized,
value: MaybeUninit::uninit(),
}
}
#[inline(always)]
pub fn initialize_once(&mut self, value: Value) -> &mut Value
{
#[cfg(debug_assertions)]
{
debug_assert_eq!(self.initialization_pattern, Self::Uninitialized);
self.initialization_pattern = Self::Initialized;
}
self.value.write(value)
}
#[inline(always)]
pub fn value(&self) -> &'static Value
{
#[cfg(debug_assertions)]
{
debug_assert_eq!(self.initialization_pattern, Self::Initialized);
}
unsafe { & * self.value.as_ptr() }
}
#[inline(always)]
pub fn value_mut(&mut self) -> &'static mut Value
{
#[cfg(debug_assertions)]
{
debug_assert_eq!(self.initialization_pattern, Self::Initialized);
}
unsafe { &mut * self.value.as_mut_ptr() }
}
}