initial

src/vso.rs

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+#![allow(unused)]
+
+use core::fmt::{Debug, Display, Formatter, UpperHex};
+use core::marker::PhantomData;
+use core::mem::transmute;
+use core::ops::{ControlFlow, Deref, DerefMut, Index, IndexMut};
+
+pub struct VirtualOffset<T, const O: usize>(PhantomData<T>);
+
+impl<T, const O: usize> VirtualOffset<T, O> {
+
+    #[inline(always)]
+    pub(crate) fn vo_as_ptr(&self) -> *mut T {
+        ((self as *const _ as usize) + O) as *mut T
+    }
+
+    #[inline(always)]
+    pub(crate) fn offset() -> usize {
+        return O;
+    }
+
+    /// gets a ref to the underlying type
+    /// just an alias for the deref trait so it doesnt need to be imported
+    pub fn r#ref(&self) -> &T {
+        self.deref()
+    }
+
+}
+
+impl<T, const O: usize> Deref for VirtualOffset<T, O> {
+    type Target = T;
+
+    #[inline(always)]
+    fn deref(&self) -> &Self::Target {
+        unsafe { transmute(((self as *const _ as usize) + O) as *const T)}
+    }
+}
+
+impl<T, const O: usize> DerefMut for VirtualOffset<T, O> {
+
+    #[inline(always)]
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        unsafe { transmute(((self as *mut _ as usize) + O) as *mut T)}
+    }
+}
+
+// ==============================
+//            Index
+// ==============================
+
+impl<I, T: Index<I>, const O: usize> Index<I> for VirtualOffset<T, O> {
+    type Output = T::Output;
+    fn index(&self, index: I) -> &Self::Output {
+        unsafe { &*self.vo_as_ptr() }.index(index)
+    }
+}
+
+impl<I, T: IndexMut<I>, const O: usize> IndexMut<I> for VirtualOffset<T, O> {
+    fn index_mut(&mut self, index: I) -> &mut Self::Output {
+        unsafe { &mut *self.vo_as_ptr() }.index_mut(index)
+    }
+}
+
+// ==============================
+//       Display + Debug
+// ==============================
+
+// Proxy the Display trait
+impl<T: Display, const O: usize> Display for VirtualOffset<T, O> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> core::fmt::Result {
+        self.deref().fmt(f)
+    }
+}
+
+// Proxy the UpperHex trait
+impl<T: UpperHex, const O: usize> UpperHex for VirtualOffset<T, O> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> core::fmt::Result {
+        self.deref().fmt(f)
+    }
+}
+
+// Proxy the Debug trait (in debug builds)
+#[cfg(not(feature="production"))]
+impl<T: Debug, const O: usize> Debug for VirtualOffset<T, O> {
+    fn fmt(&self, f: &mut Formatter<'_>) -> core::fmt::Result {
+        self.deref().fmt(f)
+    }
+}
+
+// ==============================
+//            Macro
+// ==============================
+
+#[macro_export]
+macro_rules! struct_offset {
+    ($offset:literal, $type:ty) => {
+        $crate::VirtualOffset<$type, $offset>
+    }
+}
+