Improve the style of code in lib/.

lib/src/sha1.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library crypto.sha1;
 
 import 'dart:typed_data';
 
 import 'hash.dart';
 import 'hash_base.dart';
 import 'utils.dart';
 
 /// An implementation of the [SHA-1][rfc] hash function.
 ///
 /// [rfc]: http://tools.ietf.org/html/rfc3174
 abstract class SHA1 implements Hash {
   factory SHA1() = _SHA1;
 
   SHA1 newInstance();
 }
 
 /// The concrete implementation of [SHA1].
 ///
 /// This is separate so that it can extend [HashBase] without leaking additional
 /// public memebers.
 class _SHA1 extends HashBase implements SHA1 {
+  final digest = new Uint32List(5);
+
   /// The sixteen words from the original chunk, extended to 80 words.
   ///
   /// This is an instance variable to avoid re-allocating, but its data isn't
   /// used across invocations of [updateHash].
-  final Uint32List _w;
+  final Uint32List _extended;
 
   _SHA1()
-      : _w = new Uint32List(80),
-        super(16, 5, true) {
-    h[0] = 0x67452301;
-    h[1] = 0xEFCDAB89;
-    h[2] = 0x98BADCFE;
-    h[3] = 0x10325476;
-    h[4] = 0xC3D2E1F0;
+      : _extended = new Uint32List(80),
+        super(16) {
+    digest[0] = 0x67452301;
+    digest[1] = 0xEFCDAB89;
+    digest[2] = 0x98BADCFE;
+    digest[3] = 0x10325476;
+    digest[4] = 0xC3D2E1F0;
   }
 
-  SHA1 newInstance() {
-    return new _SHA1();
-  }
+  SHA1 newInstance() => new _SHA1();
 
-  void updateHash(Uint32List m) {
-    assert(m.length == 16);
+  void updateHash(Uint32List chunk) {
+    assert(chunk.length == 16);
 
-    var a = h[0];
-    var b = h[1];
-    var c = h[2];
-    var d = h[3];
-    var e = h[4];
+    var a = digest[0];
+    var b = digest[1];
+    var c = digest[2];
+    var d = digest[3];
+    var e = digest[4];
 
     for (var i = 0; i < 80; i++) {
       if (i < 16) {
-        _w[i] = m[i];
+        _extended[i] = chunk[i];
       } else {
-        var n = _w[i - 3] ^ _w[i - 8] ^ _w[i - 14] ^ _w[i - 16];
-        _w[i] = rotl32(n, 1);
+        _extended[i] = rotl32(
+            _extended[i - 3] ^ _extended[i - 8] ^ _extended[i - 14] ^
+                _extended[i - 16],
+            1);
       }
-      var t = add32(add32(rotl32(a, 5), e), _w[i]);
+
+      var newA = add32(add32(rotl32(a, 5), e), _extended[i]);
       if (i < 20) {
-        t = add32(add32(t, (b & c) | (~b & d)), 0x5A827999);
+        newA = add32(add32(newA, (b & c) | (~b & d)), 0x5A827999);
       } else if (i < 40) {
-        t = add32(add32(t, (b ^ c ^ d)), 0x6ED9EBA1);
+        newA = add32(add32(newA, (b ^ c ^ d)), 0x6ED9EBA1);
       } else if (i < 60) {
-        t = add32(add32(t, (b & c) | (b & d) | (c & d)), 0x8F1BBCDC);
+        newA = add32(add32(newA, (b & c) | (b & d) | (c & d)), 0x8F1BBCDC);
       } else {
-        t = add32(add32(t, b ^ c ^ d), 0xCA62C1D6);
+        newA = add32(add32(newA, b ^ c ^ d), 0xCA62C1D6);
       }
 
       e = d;
       d = c;
       c = rotl32(b, 30);
       b = a;
-      a = t & MASK_32;
+      a = newA & mask32;
     }
 
-    h[0] = add32(a, h[0]);
-    h[1] = add32(b, h[1]);
-    h[2] = add32(c, h[2]);
-    h[3] = add32(d, h[3]);
-    h[4] = add32(e, h[4]);
+    digest[0] = add32(a, digest[0]);
+    digest[1] = add32(b, digest[1]);
+    digest[2] = add32(c, digest[2]);
+    digest[3] = add32(d, digest[3]);
+    digest[4] = add32(e, digest[4]);
   }
 }