make map and asyncMap generate an object if initially given an object…

… (rather than always generating an array

asyncMap.js

@@ -2,8 +2,7 @@ var asyncEach = require('std/asyncEach')
 var isList = require('std/isList')
 
 module.exports = function asyncMap(items, opts) {
-	var result = []
-	result.length = isList(items) ? items.length : Object.keys(items).length
+	var result = isList(items) ? new Array(items.length) : {}
 	var includeNullValues = !opts.filterNulls
 	var context = opts.context || this
 

each.js

@@ -1,20 +1,15 @@
-var isArray = require('./isArray'),
-	isArguments = require('./isArguments')
+var isList = require('./isList')
 
-module.exports = function(items, ctx, fn) {
+module.exports = function each(items, fn) {
 	if (!items) { return }
-	if (!fn) {
-		fn = ctx
-		ctx = this
-	}
-	if (isArray(items) || isArguments(items)) {
+	if (isList(items)) {
 		for (var i=0; i < items.length; i++) {
-			fn.call(ctx, items[i], i)
+			fn(items[i], i)
 		}
 	} else {
 		for (var key in items) {
 			if (!items.hasOwnProperty(key)) { continue }
-			fn.call(ctx, items[key], key)
+			fn(items[key], key)
 		}
 	}
 }

first.js

@@ -1,3 +1,3 @@
 module.exports = function first(arr) {
-	return arr[0]
+	return arr ? arr[0] : null
 }

map.js

@@ -1,13 +1,10 @@
 var each = require('./each')
+var isList = require('./isList')
 
-module.exports = function(items, ctx, fn) {
-	var result = []
-	if (!fn) {
-		fn = ctx
-		ctx = this
-	}
-	each(items, ctx, function(item, key) {
-		result.push(fn.call(ctx, item, key))
+module.exports = function map(obj, fn) {
+	var result = isList(obj) ? new Array(obj.length) : {}
+	each(obj, function(val, key) {
+		result[key] = fn(val, key)
 	})
 	return result
 }

toArray.js

@@ -0,0 +1,11 @@
+var identity = require('./identity')
+var each = require('./each')
+
+module.exports = function toArray(obj, fn) {
+	if (!fn) { fn = identity }
+	var result = []
+	each(obj, function(val, key) {
+		result.push(fn(val, key))
+	})
+	return result
+}

url.js

@@ -1,5 +1,6 @@
 var Class = require('./Class')
 var map = require('./map')
+var toArray = require('./toArray')
 var isArray = require('std/isArray')
 
 var URL = Class(function() {
@@ -96,7 +97,7 @@ url.query = {
 		return params
 	},
 	string:function(params) {
-		return map(params, function(val, key) {
+		return toArray(params, function(val, key) {
 			return encodeURIComponent(key) + '=' + url.query.encodeValue(val)
 		}).join('&')
 	},