js engines tend to create sparse arrays under the good when given arr…

…ay lengths at construction. Use literal [] instead

asyncMap.js

@@ -2,7 +2,7 @@ var asyncEach = require('std/asyncEach')
 var isList = require('std/isList')
 
 module.exports = function asyncMap(items, opts) {
-	var result = isList(items) ? new Array(items.length) : {}
+	var result = isList(items) ? [] : {}
 	var includeNullValues = !opts.filterNulls
 	var context = opts.context || this
 

map.js

@@ -6,7 +6,7 @@ module.exports = function map(obj, fn) {
 	if (!obj) { return null }
 	if (obj.map == Array.prototype.map) { return obj.map(fn) }
 
-	var result = isList(obj) ? new Array(obj.length) : {}
+	var result = isList(obj) ? [] : {}
 	each(obj, function(val, key) {
 		result[key] = fn(val, key)
 	})

pack.js

@@ -221,7 +221,7 @@ module.exports = function pack (format) {
                 status = isNaN(n = parseFloat(argument)) || n === -Infinity || n === +Infinity ? n : 0;
                 exp = 0;
                 len = 2 * bias + 1 + precisionBits + 3;
-                bin = new Array(len);
+                bin = [];
                 signal = (n = status !== 0 ? 0 : n) < 0;
                 n = Math.abs(n);
                 intPart = Math.floor(n);

range.js

@@ -7,7 +7,7 @@ module.exports = function range(start, stop, step) {
 
 	var length = Math.max(Math.ceil((stop - start) / step), 0)
 	var index = 0
-	var result = new Array(length)
+	var result = []
 
 	while (index < length) {
 		result[index++] = start