A drop-in replacement for Underscore.js, from the devs behind jsPerf.com, that delivers performance improvements, bug fixes, and additional features.
Lo-Dash’s performance is gained by avoiding slower native methods, instead opting for simplified non-ES5 compliant methods optimized for common usage, and by leveraging function compilation to reduce the number of overall function calls.
We’ve got API docs and unit tests.
For a list of upcoming features, check out our roadmap.
For more information check out these screencasts over Lo-Dash:
- AMD loader support
- _.bind supports "lazy" binding
- _.debounce’ed functions match _.throttle’ed functions’ return value behavior
- _.forEach is chainable
- _.groupBy accepts a third,
thisArg, argument - _.partial for more functional fun
- _.size supports returning the
lengthof string values
Lo-Dash has been tested in at least Chrome 5-19, Firefox 1.5-12, IE 6-9, Opera 9.25-11.64, Safari 3.0.4-5.1.3, Node.js 0.4.8-0.6.18, Narwhal 0.3.2, RingoJS 0.8, and Rhino 1.7RC3.
Custom builds make it easy to create lightweight versions of Lo-Dash containing only the methods you need. We handle all the method dependency and alias mapping for you.
Custom builds may be created in two ways:
- Use the
includeargument to pass the names of the methods to include in the build.
node build include=each,filter,map,noConflict
node build include="each, filter, map, noConflict"- Use the
excludeargument to pass the names of the methods to exclude from the build.
node build exclude=isNaN,isUndefined,union,zip
node build exclude="isNaN, isUndefined, union, zip"Custom builds are saved to lodash.custom.js and lodash.custom.min.js.
In browsers:
<script src="lodash.js"></script>Using npm:
npm install lodashIn Node.js and RingoJS v0.8.0+:
var _ = require('lodash');In Narwhal and RingoJS v0.7.0-:
var _ = require('lodash')._;In Rhino:
load('lodash.js');In an AMD loader like RequireJS:
require({
'paths': {
'underscore': 'path/to/lodash'
}
},
['underscore'], function(_) {
console.log(_.VERSION);
});To clone this repository including all submodules, using Git 1.6.5 or later:
git clone --recursive https://github.com/bestiejs/lodash.git
cd lodash.jsFor older Git versions, just use:
git clone https://github.com/bestiejs/lodash.git
cd lodash
git submodule update --init- Ensure
_.groupByadds values to own, not inherited, properties [test] - Ensure
_.throttleworks when called in tight loops [#502, test] - Fix Firefox, IE, Opera, and Safari object iteration bugs [#376, test, test, test, test, test, test]
- Handle arrays with
undefinedvalues correctly in IE < 9 [#601] - Methods should work on pages with incorrectly shimmed native methods [#7, test]
- Register as AMD module, but still export to global [#431, test]
_.forEachshould be chainable [#142, test]_isNaN(new Number(NaN))should returntrue[test]_.reduceRightshould pass correct callback arguments when iterating objects [test]_.sizeshould return thelengthof string values [test]
_.bind_.bindAll_.clone_.compact_.contains,_.include_.defaults_.defer_.difference_.each_.escape_.every,_.all_.extend_.filter,_.select_.find,_.detect_.flatten_.forEach,_.each_.functions,_.methods_.groupBy_.indexOf_.intersection_.invoke_.isEmpty_.isEqual_.isFinite_.isObject_.isString_.keys_.lastIndexOf_.map,_.collect_.max_.memoize_.min_.mixin_.pick_.pluck_.reduce,_.foldl,_.inject_.reject_.result_.shuffle_.some,_.any_.sortBy_.sortedIndex_.template_.throttle_.toArray_.union_.uniq,_.unique_.values_.without_.wrap_.zip- plus all
_(...)method wrappers
- Adjusted the Lo-Dash export order for r.js
- Ensured
_.groupByvalues are added to own, not inherited, properties - Made
_.bindfollow ES5 spec to support a popular Backbone.js pattern - Removed the alias
intersect - Simplified
_.bind,_.flatten,_.groupBy,_.max, and_.min
- Added custom build options
- Added default
_.templateSettings.variablevalue - Added "lazy bind" support to
_.bind - Added native method overwrite detection to avoid bad native shims
- Added support for more AMD build optimizers and aliasing as the "underscore" module
- Added
thisArgargument to_.groupBy - Added whitespace to compiled strings
- Added
_.partialmethod - Commented the
iterationFactoryoptions object - Ensured
_.maxand_.minsupport extremely large arrays - Ensured
_.throttleworks in tight loops - Fixed IE < 9
[DontEnum]bug and Firefox < 3.6, Opera > 9.50 - Opera < 11.60, and Safari < 5.1’s prototype property iteration bug - Inlined
_.isFunctioncalls. - Made
_.debounce’ed functions match_.throttle’ed functions’ return value behavior - Made
_.escapeno longer translate the ">" character - Fixed
clearTimeouttypo - Simplified all methods in the "Arrays" category
- Optimized
_.debounce,_.escape,_.flatten,_.forEach,_.groupBy,_.intersection,_.invoke,_.isObject,_.max,_.min,_.pick,_.shuffle,_.sortedIndex,_.template,_.throttle,_.union,_.uniq
- Initial release
Lo-Dash is part of the BestieJS "Best in Class" module collection. This means we promote solid browser/environment support, ES5 precedents, unit testing, and plenty of documentation.
