Migrate to Rust 2021

Cargo.toml

@@ -8,7 +8,7 @@ authors = [
     "Daira Hopwood <daira@electriccoin.co>",
     "Jack Grigg <jack@electriccoin.co>",
 ]
-edition = "2018"
+edition = "2021"
 rust-version = "1.56"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/zcash/pasta_curves"

src/arithmetic/fields.rs

@@ -13,7 +13,7 @@ use core::assert;
 #[cfg(feature = "sqrt-table")]
 use alloc::{boxed::Box, vec::Vec};
 #[cfg(feature = "sqrt-table")]
-use core::{convert::TryInto, marker::PhantomData};
+use core::marker::PhantomData;
 
 const_assert!(size_of::<usize>() >= 4);
 

src/fields/fp.rs

@@ -1,4 +1,3 @@
-use core::convert::TryInto;
 use core::fmt;
 use core::ops::{Add, Mul, Neg, Sub};
 

src/fields/fq.rs

@@ -1,4 +1,3 @@
-use core::convert::TryInto;
 use core::fmt;
 use core::ops::{Add, Mul, Neg, Sub};