perf: use dedicated Iterator methods instead of Vec pushing

Signed-off-by: ljedrz <ljedrz@gmail.com>
ljedrz · Oct 1, 2020 · c358282 · c358282
1 parent 24b8bb5
commit c358282
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Showing 5 changed files with 9 additions and 27 deletions.
diff --git a/algorithms/src/encryption/tests.rs b/algorithms/src/encryption/tests.rs
@@ -30,12 +30,7 @@ type TestEncryptionScheme = GroupEncryption<EdwardsProjective>;
 pub const ITERATIONS: usize = 1000;
 
 fn generate_input<G: Group + ProjectiveCurve, R: Rng>(input_size: usize, rng: &mut R) -> Vec<G> {
-    let mut input = vec![];
-    for _ in 0..input_size {
-        input.push(G::rand(rng))
-    }
-
-    input
+    (0..input_size).map(|_| G::rand(rng)).collect()
 }
 
 #[test]

diff --git a/algorithms/src/fft/polynomial/dense.rs b/algorithms/src/fft/polynomial/dense.rs
@@ -140,10 +140,7 @@ impl<F: Field> DensePolynomial<F> {
     /// Outputs a polynomial of degree `d` where each coefficient is sampled uniformly at random
     /// from the field `F`.
     pub fn rand<R: Rng>(d: usize, rng: &mut R) -> Self {
-        let mut random_coeffs = Vec::new();
-        for _ in 0..(d + 1) {
-            random_coeffs.push(F::rand(rng));
-        }
+        let random_coeffs = (0..(d + 1)).map(|_| F::rand(rng)).collect();
         Self::from_coefficients_vec(random_coeffs)
     }
 }

diff --git a/models/src/gadgets/utilities/uint/unsigned_integer.rs b/models/src/gadgets/utilities/uint/unsigned_integer.rs
@@ -100,11 +100,7 @@ pub trait UInt: Debug + Clone + PartialOrd + Eq + PartialEq {
 impl UInt8 {
     /// Construct a constant vector of `UInt8` from a vector of `u8`
     pub fn constant_vec(values: &[u8]) -> Vec<Self> {
-        let mut result = Vec::new();
-        for value in values {
-            result.push(UInt8::constant(*value));
-        }
-        result
+        values.iter().copied().map(UInt8::constant).collect()
     }
 
     pub fn alloc_vec<F, CS, T>(mut cs: CS, values: &[T]) -> Result<Vec<Self>, SynthesisError>

diff --git a/rpc/src/rpc_impl.rs b/rpc/src/rpc_impl.rs
@@ -305,11 +305,7 @@ impl RpcFunctions for RpcImpl {
         // Create a temporary tokio runtime to make an asynchronous function call
         let peer_book = Runtime::new()?.block_on(self.server_context.peer_book.read());
 
-        let mut peers = vec![];
-
-        for peer in peer_book.get_connected().keys() {
-            peers.push(*peer);
-        }
+        let peers = peer_book.get_connected().keys().cloned().collect();
 
         Ok(PeerInfo { peers })
     }

diff --git a/utilities/derives/src/lib.rs b/utilities/derives/src/lib.rs
@@ -138,13 +138,11 @@ fn impl_deserialize_field(ty: &Type) -> (TokenStream, TokenStream) {
     // Check if type is a tuple.
     match ty {
         Type::Tuple(tuple) => {
-            let mut compressed_fields = Vec::new();
-            let mut uncompressed_fields = Vec::new();
-            for elem_ty in tuple.elems.iter() {
-                let (compressed, uncompressed) = impl_deserialize_field(elem_ty);
-                compressed_fields.push(compressed);
-                uncompressed_fields.push(uncompressed);
-            }
+            let (compressed_fields, uncompressed_fields): (Vec<_>, Vec<_>) = tuple
+                .elems
+                .iter()
+                .map(|elem_ty| impl_deserialize_field(elem_ty))
+                .unzip();
             (
                 quote! { (#(#compressed_fields)*), },
                 quote! { (#(#uncompressed_fields)*), },