Pre-RFC: Read::read_into_uninitialized

libs
7

It would be better to have an ‘uninitialized buffer’ trait rather than forcing every Read impl to take care of it (and use unsafe code). Something like

unsafe trait UninitializedBuffer<T> {
    fn get(&mut self) -> *mut [T];
    unsafe fn did_fill(&mut self, size: usize);
    // + safe helper methods to append, etc.
}
// example
unsafe impl<T> UninitializedBuffer<T> for Vec<T> {
    fn get(&mut self) -> *mut [T] {
        unsafe {
            slice::from_raw_parts_mut(self.as_mut_ptr().offset(self.len() as isize),
                                      self.capacity() - self.len()) as *mut [T]
        }
    }
    unsafe fn did_fill(&mut self, size: usize) {
        self.set_len(self.len() + size);
    }
}
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