make the new faster isEmpty a little safer too

This commit is contained in:
Jeremy Ashkenas
2010-02-24 12:43:57 -05:00
parent 2c8fbe7875
commit 7824d63ce8
3 changed files with 90 additions and 90 deletions

View File

@@ -4,7 +4,6 @@
<meta http-equiv="content-type" content="text/html;charset=UTF-8" /> <meta http-equiv="content-type" content="text/html;charset=UTF-8" />
<meta http-equiv="X-UA-Compatible" content="chrome=1"> <meta http-equiv="X-UA-Compatible" content="chrome=1">
<title>Underscore.js</title> <title>Underscore.js</title>
<script src="underscore.js"></script>
<style> <style>
body { body {
font-size: 16px; font-size: 16px;
@@ -1288,5 +1287,8 @@ _([1, 2, 3]).value();
</div> </div>
<!-- Include Underscore, so you can play with it in the console. -->
<script type="text/javascript" src="underscore.js"></script>
</body> </body>
</html> </html>

View File

@@ -60,6 +60,7 @@ $(document).ready(function() {
ok(_.isEmpty([]), '[] is empty'); ok(_.isEmpty([]), '[] is empty');
ok(!_.isEmpty({one : 1}), '{one : 1} is not empty'); ok(!_.isEmpty({one : 1}), '{one : 1} is not empty');
ok(_.isEmpty({}), '{} is empty'); ok(_.isEmpty({}), '{} is empty');
ok(_.isEmpty(new RegExp('')), 'objects with prototype properties are empty');
ok(_.isEmpty(null), 'null is empty'); ok(_.isEmpty(null), 'null is empty');
ok(_.isEmpty(), 'undefined is empty'); ok(_.isEmpty(), 'undefined is empty');
@@ -102,7 +103,7 @@ $(document).ready(function() {
ok(_.isArguments(args), 'but the arguments object is an arguments object'); ok(_.isArguments(args), 'but the arguments object is an arguments object');
ok(!_.isArguments(_.toArray(args)), 'but not when it\'s converted into an array'); ok(!_.isArguments(_.toArray(args)), 'but not when it\'s converted into an array');
ok(!_.isArguments([1,2,3]), 'and not vanilla arrays.'); ok(!_.isArguments([1,2,3]), 'and not vanilla arrays.');
ok(_.isArguments(iArguments), 'event from another frame'); ok(_.isArguments(iArguments), 'even from another frame');
}); });
test("objects: isArray", function() { test("objects: isArray", function() {

View File

@@ -67,18 +67,17 @@
// The cornerstone, an each implementation. // The cornerstone, an each implementation.
// Handles objects implementing forEach, arrays, and raw objects. // Handles objects implementing forEach, arrays, and raw objects.
// Delegates to JavaScript 1.6's native forEach if available. // Delegates to JavaScript 1.6's native forEach if available.
var each = var each = _.forEach = function(obj, iterator, context) {
_.forEach = function(obj, iterator, context) {
var index = 0; var index = 0;
try { try {
if (obj.forEach === nativeForEach) { if (obj.forEach === nativeForEach) {
obj.forEach(iterator, context); obj.forEach(iterator, context);
} else if (_.isNumber(obj.length)) { } else if (_.isNumber(obj.length)) {
for (var i=0, l=obj.length; i<l; i++) iterator.call(context, obj[i], i, obj); for (var i = 0, l = obj.length; i < l; i++) iterator.call(context, obj[i], i, obj);
} else { } else {
for (var key in obj) for (var key in obj) {
if (hasOwnProperty.call(obj, key)) if (hasOwnProperty.call(obj, key)) iterator.call(context, obj[key], key, obj);
iterator.call(context, obj[key], key, obj); }
} }
} catch(e) { } catch(e) {
if (e != breaker) throw e; if (e != breaker) throw e;
@@ -339,7 +338,7 @@
var args = _.toArray(arguments); var args = _.toArray(arguments);
var length = _.max(_.pluck(args, 'length')); var length = _.max(_.pluck(args, 'length'));
var results = new Array(length); var results = new Array(length);
for (var i=0; i<length; i++) results[i] = _.pluck(args, String(i)); for (var i = 0; i < length; i++) results[i] = _.pluck(args, String(i));
return results; return results;
}; };
@@ -349,7 +348,7 @@
// Delegates to JavaScript 1.8's native indexOf if available. // Delegates to JavaScript 1.8's native indexOf if available.
_.indexOf = function(array, item) { _.indexOf = function(array, item) {
if (array.indexOf === nativeIndexOf) return array.indexOf(item); if (array.indexOf === nativeIndexOf) return array.indexOf(item);
for (var i=0, l=array.length; i<l; i++) if (array[i] === item) return i; for (var i = 0, l = array.length; i < l; i++) if (array[i] === item) return i;
return -1; return -1;
}; };
@@ -513,7 +512,7 @@
// Is a given array or object empty? // Is a given array or object empty?
_.isEmpty = function(obj) { _.isEmpty = function(obj) {
if (_.isArray(obj)) return obj.length === 0; if (_.isArray(obj)) return obj.length === 0;
for (var k in obj) return false; for (var key in obj) if (hasOwnProperty.call(obj, key)) return false;
return true; return true;
}; };
@@ -588,11 +587,9 @@
return value; return value;
}; };
// run a function n times. // Run a function n times.
// looks good in wrapper form: _.times = function (n, iterator, context) {
// _(3).times(alert) for (var i = 0; i < n; i++) iterator.call(context, i);
_.times = function (n, fn, context) {
for (var i = 0; i < n; i++) fn.call(context, i);
}; };
// Break out of the middle of an iteration. // Break out of the middle of an iteration.