Partial cloning

[serle]

I'm attempting to build a lenient parser/deserializer that can parse from json / yaml into an ir, which can self heal & have more dynamic default values and business rules. I'm finding that the best way to deserialize off the ir is to detect end events and build partials depth first. But there can be some backtracking, so I would like to leave the Partial active, for additional mutation, but obtain a heap_value. Something that effectively does a partial.clone().build() i.e. non-consuming heap_value builder. I was wondering if this would be possible.

[serle]

Hoping not to do this but this seems to work for me:

fn copy_and_build_partial(&self, original: &Partial<'static>) -> Result<HeapValue<'static>, BuildError> {
      use std::mem::{self, MaybeUninit};
      use std::ptr;

      unsafe {
          // Create uninitialized memory using MaybeUninit
          let mut copy_storage = MaybeUninit::<Partial<'static>>::uninit();

          // Copy original's bytes to our storage
          ptr::copy_nonoverlapping(
              original as *const Partial<'static> as *const u8,
              copy_storage.as_mut_ptr() as *mut u8,
              mem::size_of::<Partial<'static>>()
          );

          // Transmute and immediately build
          let mut copied_partial = copy_storage.assume_init();
          copied_partial.build() // Return HeapValue directly
      }
  }