Refactor loop variables

PR-URL: #370

Author: tshemsedinov

lib/array.js

@@ -33,8 +33,7 @@ const map = (
     if (count === len) done(null, result);
   };
 
-  let i;
-  for (i = 0; i < len; i++) {
+  for (let i = 0; i < len; i++) {
     fn(items[i], next.bind(null, i));
   }
 };
@@ -72,17 +71,15 @@ const filter = (
     if (count === len) {
       const result = new Array(suitable);
       let pos = 0;
-      let i, val;
-      for (i = 0; i < len; i++) {
-        val = data[i];
+      for (let i = 0; i < len; i++) {
+        const val = data[i];
         if (val !== rejected) result[pos++] = val;
       }
       done(null, result);
     }
   };
 
-  let i;
-  for (i = 0; i < len; i++) {
+  for (let i = 0; i < len; i++) {
     fn(items[i], next.bind(null, i));
   }
 };
@@ -161,8 +158,7 @@ const each = (
     if (count === len) done(null);
   };
 
-  let i;
-  for (i = 0; i < len; i++) {
+  for (let i = 0; i < len; i++) {
     fn(items[i], next);
   }
 };
@@ -228,8 +224,7 @@ const find = (
     if (index === last) done(null);
   };
 
-  let i;
-  for (i = 0; i < len; i++) {
+  for (let i = 0; i < len; i++) {
     fn(items[i], next.bind(null, i));
   }
 };
@@ -261,8 +256,7 @@ const every = (
     if (proceedItemsCount === len) done(null, true);
   };
 
-  let item;
-  for (item of items) fn(item, finish);
+  for (const item of items) fn(item, finish);
 };
 
 const some = (

lib/composition.js

@@ -119,10 +119,9 @@ Composition.prototype.parallel = function() {
   const fns = this.fns;
   const len = this.len;
   const context = this.context;
-  let i, fn, fc;
-  for (i = 0; i < len; i++) {
-    fn = fns[i];
-    fc = Array.isArray(fn) ? compose(fn) : fn;
+  for (let i = 0; i < len; i++) {
+    const fn = fns[i];
+    const fc = Array.isArray(fn) ? compose(fn) : fn;
     fc(context, next);
   }
 };

lib/control.js

@@ -47,8 +47,7 @@ const parallel = (
     if (++counter === len) done(null, context);
   };
 
-  let fn;
-  for (fn of fns) {
+  for (const fn of fns) {
     // fn may be array of function
     const finish = finishFn.bind(null, fn);
     if (fn.length === 2) fn(context, finish);