add a helper module with a project_ref function

Author: BennoLossin

src/helper.rs

@@ -0,0 +1,10 @@
+use core::ptr;
+
+use crate::marker::Field;
+
+pub fn project_ref<F: Field>(r: &F::Base) -> &F::Type
+where
+    F::Type: Sized,
+{
+    unsafe { &*ptr::from_ref(r).byte_add(F::OFFSET).cast() }
+}

src/lib.rs

@@ -3,5 +3,6 @@
 #![warn(unsafe_op_in_unsafe_fn)]
 
 pub mod compat;
+pub mod helper;
 pub mod marker;
 pub mod ops;