Get rid of Qr::new

It's useless in const context because we have all possible instances
as conts already.

Also: improve iter() documentation and make Qr::NAMES pub.

src/_sqrid.rs

@@ -231,19 +231,8 @@ impl Qr {
     /// [`Qr`].
     const INVERSE: [usize; 9] = [7, 0, 1, 6, usize::MAX, 2, 5, 4, 3];
 
-    /// Create a new [`Qr`] instance.
-    /// Can be used in const context.
-    /// Bounds are checked at compile-time, if possible.
-    pub const fn new<const DX: i16, const DY: i16>() -> Self {
-        // Trick for compile-time check of X and Y:
-        const ASSERT_FALSE: [(); 1] = [(); 1];
-        let _ =
-            ASSERT_FALSE[(DX < -1 || DX > 1 || DY < -1 || DY > 1 || (DX == 0 && DY == 0)) as usize];
-        Self { dx: DX, dy: DY }
-    }
-
     /// The names of all corresponding values
-    const NAMES: [&'static str; 8] = ["N", "NE", "E", "SE", "S", "SW", "W", "NW"];
+    pub const NAMES: [&'static str; 8] = ["N", "NE", "E", "SE", "S", "SW", "W", "NW"];
 
     /// Returns true if the Qr is a diagonal: NE, SE, SW or NW.
     pub const fn is_diagonal(&self) -> bool {
@@ -252,6 +241,9 @@ impl Qr {
 
     /// Returns an iterator that returns all possible values for the
     /// [`Qr`] type used, in clockwise order.
+    ///
+    /// This function takes a generic const argument `D` that
+    /// indicates if diagonals should be in the iteration or not.
     pub fn iter<const D: bool>() -> QrIterator<D> {
         QrIterator::<D>::default()
     }

src/lib.rs

@@ -95,17 +95,6 @@
 //!       Ok(())
 //!   }
 //!   ```
-//! - Calling [`Qr::new`], which checks the bounds in const contexts:
-//!   ```rust
-//!   use sqrid::Qr;
-//!   const DOWNRIGHT : Qr = Qr::new::<1, 1>();
-//!   ```
-//!   The following, for instance, doesn't compile due to the
-//!   arguments not being units:
-//!   ```compile_fail
-//!   use sqrid::Qr;
-//!   const DOWNRIGHT2 : Qr = Qr::new::<2, 2>();
-//!   ```
 //! - Calling [`Qr::iter`] to iterate all directions:
 //!   ```rust
 //!   for qr in sqrid::Qr::iter::<true>() {

tests/qr_tests.rs

@@ -12,12 +12,10 @@ use std::convert::TryFrom;
 fn test_basic() -> Result<()> {
     let qr0 = Qr::default();
     let qr1 = Qr::N;
-    let qr2 = Qr::new::<0, -1>();
     assert_eq!(qr0, qr1);
-    assert_eq!(qr0, qr2);
     assert_eq!(<(i16, i16)>::from(qr1), (0, -1));
-    let qr3 = Qr::try_from((-1_i16, 0_i16));
-    assert_eq!(qr3, Ok(Qr::W));
+    let qr2 = Qr::try_from((-1_i16, 0_i16));
+    assert_eq!(qr2, Ok(Qr::W));
     Ok(())
 }