1. Underscore.js
an introduction

2. Collections in JS are a pain!

4. What do I get?
_.functions(_) => [ 'after', 'all', 'any', 'bind', 'bindAll', 'clone',
'compact', 'compose', 'contains', 'debounce', 'defaults',
'defer', 'delay', 'difference', 'each', 'escape'', 'extend', 'filter',
'find', 'first', 'flatten', 'functions', 'groupBy', 'head', 'identity',
'include', 'indexOf', 'initial', 'intersect', 'intersection', 'invoke',
'isArguments', 'isArray', 'isBoolean', 'isDate', 'isElement',
'isEmpty', 'isEqual', 'isFunction', 'isNaN', 'isNull', 'isNumber',
'isObject', 'isRegExp', 'isString', 'isUndefined', 'keys', 'last',
'lastIndexOf', 'map', 'max', 'memoize', 'methods', 'min',
'mixin', 'noConflict', 'once', 'pluck', 'range', 'reduce',
'reduceRight', 'reject', 'rest', 'select', 'shuffle', 'size', 'some',
'sortBy', 'sortedIndex', 'tail', 'tap', 'template', 'throttle', 'times',
'toArray', 'union', 'uniq', 'unique', 'uniqueId', 'values',
'without', 'wrap', 'zip' ]

5. Functional vs Object-Oriented
Object-Oriented style:
_(arr).pluck('name')
Functional style:
_.pluck(arr, 'name')

6. Sorting an array of objects
var ppl = [ { name: 'Alice', age: 20 }, { name:
'Bob', age: 18 }, { name: 'Charles', age: 23 } ]
_.sortBy(ppl, function(x){ return -1 * x.age })
=> [{"name":"Charles","age":23},
{"name":"Alice","age":20},
{"name":"Bob","age":18}]

7. Chaining multiple functions
var ppl = [ { name: 'Alice', age: 20 }, { name:
'Bob', age: 18 }, { name: 'Charles', age: 23 }, {
name: 'Roberto', age:21 }]
_(ppl).chain()
.reject(function(x) { return /ob/i.test(x.name) })
.sortBy(function(x) { return -1 * x.age })
.pluck('name').value()
=> ["Charles", "Alice" ]

8. Using "range" and "reduce" to make
a factorial function
_.range(1,11) = [1,2,3,4,5,6,7,8,9,10]
var fac = function(x) {
return _.reduce(_.range(1,x+1),
function(total, y) { return total * y })
}

9. Array/object equality
['hello'] == ['hello']
=> false
{foo:'bar'} == {foo:'bar'}
=> false
_.isEqual(['hello'], ['hello'])
=> true
_.isEqual({foo:'bar'}, {foo:'bar'})

10. "Inheritance", _-style
var foo = { one: 1, two: 2 }
var bar = { three: 3 }
_.extend(foo,bar)
=> {"one":1,"two":2,"three":3}

11. Throttling
var throttled = _.throttle(updatePosition, 100);
$(window).scroll(throttled);

12. Places you can use it

13. Thanks!
Sebastian Motraghi
@seb_m http://blog.motraghi.us
@xoxco http://xoxco.com