Move hashtocurve module into pasta module.

src/arithmetic.rs

@@ -2,15 +2,13 @@
 //! field and polynomial arithmetic.
 
 use crossbeam_utils::thread;
-use ff::Field;
+pub use ff::Field;
 
 mod curves;
 mod fields;
-mod hashtocurve;
 
 pub use curves::*;
 pub use fields::*;
-pub use hashtocurve::*;
 
 /// This represents an element of a group with basic operations that can be
 /// performed. This allows an FFT implementation (for example) to operate

src/pasta.rs

@@ -6,11 +6,13 @@ mod macros;
 mod curves;
 mod fields;
 
+mod hashtocurve;
 pub mod pallas;
 pub mod vesta;
 
 pub use curves::*;
 pub use fields::*;
+use hashtocurve::*;
 
 #[test]
 fn test_endo_consistency() {

src/pasta/hashtocurve.rs

@@ -6,7 +6,7 @@ use core::fmt::Debug;
 use core::marker::PhantomData;
 use subtle::ConstantTimeEq;
 
-use super::{Curve, CurveAffine, Field, FieldExt};
+use crate::arithmetic::{Curve, CurveAffine, Field, FieldExt};
 
 /// Implementation of the "simplified SWU" hashing to short Weierstrass curves
 /// with a = 0. Internally uses SHAKE128.

src/pasta/pallas.rs

@@ -2,8 +2,8 @@
 
 use lazy_static::lazy_static;
 
+use super::SimplifiedSWUWithDegree3Isogeny;
 use super::{Ep, EpAffine, Fp, Fq, IsoEp, IsoEpAffine};
-use crate::arithmetic::SimplifiedSWUWithDegree3Isogeny;
 
 /// The base field of the Pallas and iso-Pallas curves.
 pub type Base = Fp;

src/pasta/vesta.rs

@@ -2,8 +2,8 @@
 
 use lazy_static::lazy_static;
 
+use super::SimplifiedSWUWithDegree3Isogeny;
 use super::{Eq, EqAffine, Fp, Fq, IsoEq, IsoEqAffine};
-use crate::arithmetic::SimplifiedSWUWithDegree3Isogeny;
 
 /// The base field of the Vesta and iso-Vesta curves.
 pub type Base = Fq;