Underscore.js 1.3.2
(c) 2009-2012 Jeremy Ashkenas, DocumentCloud Inc.
Underscore is freely distributable under the MIT license.
Portions of Underscore are inspired or borrowed from Prototype,
@@ -31,7 +31,7 @@
exports._ = _;
} else {
root['_'] = _;
- }
|
| Current version. | |
Collection Functions | |
| The cornerstone, an each implementation, aka forEach.
+ } |
| Current version. | |
Collection Functions | |
| The cornerstone, an each implementation, aka forEach.
Handles objects with the built-in forEach, arrays, and raw objects.
Delegates to ECMAScript 5's native forEach if available. | var each = _.each = _.forEach = function(obj, iterator, context) {
if (obj == null) return;
@@ -122,7 +122,7 @@
each(obj, function(value, index, list) {
if (!(result = result && iterator.call(context, value, index, list))) return breaker;
});
- return result;
+ return !!result;
}; |
| Determine if at least one element in the object matches a truth test.
Delegates to ECMAScript 5's native some if available.
Aliased as any. | var any = _.some = _.any = function(obj, iterator, context) {
@@ -151,7 +151,7 @@
}; |
| Convenience version of a common use case of map: fetching a property. | _.pluck = function(obj, key) {
return _.map(obj, function(value){ return value[key]; });
}; |
| Return the maximum element or (element-based computation). | _.max = function(obj, iterator, context) {
- if (!iterator && _.isArray(obj)) return Math.max.apply(Math, obj);
+ if (!iterator && _.isArray(obj) && obj[0] === +obj[0]) return Math.max.apply(Math, obj);
if (!iterator && _.isEmpty(obj)) return -Infinity;
var result = {computed : -Infinity};
each(obj, function(value, index, list) {
@@ -160,7 +160,7 @@
});
return result.value;
}; |
| Return the minimum element (or element-based computation). | _.min = function(obj, iterator, context) {
- if (!iterator && _.isArray(obj)) return Math.min.apply(Math, obj);
+ if (!iterator && _.isArray(obj) && obj[0] === +obj[0]) return Math.min.apply(Math, obj);
if (!iterator && _.isEmpty(obj)) return Infinity;
var result = {computed : Infinity};
each(obj, function(value, index, list) {
@@ -171,16 +171,13 @@
}; |
| Shuffle an array. | _.shuffle = function(obj) {
var shuffled = [], rand;
each(obj, function(value, index, list) {
- if (index == 0) {
- shuffled[0] = value;
- } else {
- rand = Math.floor(Math.random() * (index + 1));
- shuffled[index] = shuffled[rand];
- shuffled[rand] = value;
- }
+ rand = Math.floor(Math.random() * (index + 1));
+ shuffled[index] = shuffled[rand];
+ shuffled[rand] = value;
});
return shuffled;
- }; |
| Sort the object's values by a criterion produced by an iterator. | _.sortBy = function(obj, iterator, context) {
+ }; |
| Sort the object's values by a criterion produced by an iterator. | _.sortBy = function(obj, val, context) {
+ var iterator = _.isFunction(val) ? val : function(obj) { return obj[val]; };
return _.pluck(_.map(obj, function(value, index, list) {
return {
value : value,
@@ -188,6 +185,8 @@
};
}).sort(function(left, right) {
var a = left.criteria, b = right.criteria;
+ if (a === void 0) return 1;
+ if (b === void 0) return -1;
return a < b ? -1 : a > b ? 1 : 0;
}), 'value');
}; |
| Groups the object's values by a criterion. Pass either a string attribute
@@ -208,17 +207,17 @@
iterator(array[mid]) < iterator(obj) ? low = mid + 1 : high = mid;
}
return low;
- }; |
| Safely convert anything iterable into a real, live array. | _.toArray = function(iterable) {
- if (!iterable) return [];
- if (iterable.toArray) return iterable.toArray();
- if (_.isArray(iterable)) return slice.call(iterable);
- if (_.isArguments(iterable)) return slice.call(iterable);
- return _.values(iterable);
+ }; |
| Safely convert anything iterable into a real, live array. | _.toArray = function(obj) {
+ if (!obj) return [];
+ if (_.isArray(obj)) return slice.call(obj);
+ if (_.isArguments(obj)) return slice.call(obj);
+ if (obj.toArray && _.isFunction(obj.toArray)) return obj.toArray();
+ return _.values(obj);
}; |
| Return the number of elements in an object. | _.size = function(obj) {
- return _.toArray(obj).length;
+ return _.isArray(obj) ? obj.length : _.keys(obj).length;
}; |
Array Functions | |
| Get the first element of an array. Passing n will return the first N
-values in the array. Aliased as head. The guard check allows it to work
-with _.map. | _.first = _.head = function(array, n, guard) {
+values in the array. Aliased as head and take. The guard check
+allows it to work with _.map. | _.first = _.head = _.take = function(array, n, guard) {
return (n != null) && !guard ? slice.call(array, 0, n) : array[0];
}; |
| Returns everything but the last entry of the array. Especcialy useful on
the arguments object. Passing n will return all the values in
@@ -251,19 +250,19 @@
been sorted, you have the option of using a faster algorithm.
Aliased as unique. | _.uniq = _.unique = function(array, isSorted, iterator) {
var initial = iterator ? _.map(array, iterator) : array;
- var result = [];
- _.reduce(initial, function(memo, el, i) {
- if (0 == i || (isSorted === true ? _.last(memo) != el : !_.include(memo, el))) {
- memo[memo.length] = el;
- result[result.length] = array[i];
+ var results = []; |
| The isSorted flag is irrelevant if the array only contains two elements. | if (array.length < 3) isSorted = true;
+ _.reduce(initial, function (memo, value, index) {
+ if (isSorted ? _.last(memo) !== value || !memo.length : !_.include(memo, value)) {
+ memo.push(value);
+ results.push(array[index]);
}
return memo;
}, []);
- return result;
- }; |
| Produce an array that contains the union: each distinct element from all of
+ return results;
+ }; |
| Produce an array that contains the union: each distinct element from all of
the passed-in arrays. | _.union = function() {
return _.uniq(_.flatten(arguments, true));
- }; |
| Produce an array that contains every item shared between all the
+ }; |
| Produce an array that contains every item shared between all the
passed-in arrays. (Aliased as "intersect" for back-compat.) | _.intersection = _.intersect = function(array) {
var rest = slice.call(arguments, 1);
return _.filter(_.uniq(array), function(item) {
@@ -271,18 +270,18 @@
return _.indexOf(other, item) >= 0;
});
});
- }; |
| Take the difference between one array and a number of other arrays.
+ }; |
| Take the difference between one array and a number of other arrays.
Only the elements present in just the first array will remain. | _.difference = function(array) {
- var rest = _.flatten(slice.call(arguments, 1));
+ var rest = _.flatten(slice.call(arguments, 1), true);
return _.filter(array, function(value){ return !_.include(rest, value); });
- }; |
| Zip together multiple lists into a single array -- elements that share
+ }; |
| Zip together multiple lists into a single array -- elements that share
an index go together. | _.zip = function() {
var args = slice.call(arguments);
var length = _.max(_.pluck(args, 'length'));
var results = new Array(length);
for (var i = 0; i < length; i++) results[i] = _.pluck(args, "" + i);
return results;
- }; |
| If the browser doesn't supply us with indexOf (I'm looking at you, MSIE),
+ }; |
| If the browser doesn't supply us with indexOf (I'm looking at you, MSIE),
we need this function. Return the position of the first occurrence of an
item in an array, or -1 if the item is not included in the array.
Delegates to ECMAScript 5's native indexOf if available.
@@ -297,13 +296,13 @@
if (nativeIndexOf && array.indexOf === nativeIndexOf) return array.indexOf(item);
for (i = 0, l = array.length; i < l; i++) if (i in array && array[i] === item) return i;
return -1;
- }; |
| Delegates to ECMAScript 5's native lastIndexOf if available. | _.lastIndexOf = function(array, item) {
+ }; |
| Delegates to ECMAScript 5's native lastIndexOf if available. | _.lastIndexOf = function(array, item) {
if (array == null) return -1;
if (nativeLastIndexOf && array.lastIndexOf === nativeLastIndexOf) return array.lastIndexOf(item);
var i = array.length;
while (i--) if (i in array && array[i] === item) return i;
return -1;
- }; |
| Generate an integer Array containing an arithmetic progression. A port of
+ }; |
| Generate an integer Array containing an arithmetic progression. A port of
the native Python range() function. See
the Python documentation. | _.range = function(start, stop, step) {
if (arguments.length <= 1) {
@@ -322,7 +321,7 @@
}
return range;
- }; |
Function (ahem) Functions | |
| Reusable constructor function for prototype setting. | |
| Create a function bound to a given object (assigning this, and arguments,
+ }; |
Function (ahem) Functions | |
| Reusable constructor function for prototype setting. | |
| Create a function bound to a given object (assigning this, and arguments,
optionally). Binding with arguments is also known as curry.
Delegates to ECMAScript 5's native Function.bind if available.
We check for func.bind first, to fail fast when func is undefined. | _.bind = function bind(func, context) {
@@ -338,29 +337,29 @@
if (Object(result) === result) return result;
return self;
};
- }; |
| Bind all of an object's methods to that object. Useful for ensuring that
+ }; |
| Bind all of an object's methods to that object. Useful for ensuring that
all callbacks defined on an object belong to it. | _.bindAll = function(obj) {
var funcs = slice.call(arguments, 1);
if (funcs.length == 0) funcs = _.functions(obj);
each(funcs, function(f) { obj[f] = _.bind(obj[f], obj); });
return obj;
- }; |
| Memoize an expensive function by storing its results. | _.memoize = function(func, hasher) {
+ }; |
| Memoize an expensive function by storing its results. | _.memoize = function(func, hasher) {
var memo = {};
hasher || (hasher = _.identity);
return function() {
var key = hasher.apply(this, arguments);
return _.has(memo, key) ? memo[key] : (memo[key] = func.apply(this, arguments));
};
- }; |
| Delays a function for the given number of milliseconds, and then calls
+ }; |
| Delays a function for the given number of milliseconds, and then calls
it with the arguments supplied. | _.delay = function(func, wait) {
var args = slice.call(arguments, 2);
- return setTimeout(function(){ return func.apply(func, args); }, wait);
- }; |
| Defers a function, scheduling it to run after the current call stack has
+ return setTimeout(function(){ return func.apply(null, args); }, wait);
+ }; |
| Defers a function, scheduling it to run after the current call stack has
cleared. | _.defer = function(func) {
return _.delay.apply(_, [func, 1].concat(slice.call(arguments, 1)));
- }; |
| Returns a function, that, when invoked, will only be triggered at most once
+ }; |
| Returns a function, that, when invoked, will only be triggered at most once
during a given window of time. | _.throttle = function(func, wait) {
- var context, args, timeout, throttling, more;
+ var context, args, timeout, throttling, more, result;
var whenDone = _.debounce(function(){ more = throttling = false; }, wait);
return function() {
context = this; args = arguments;
@@ -373,25 +372,28 @@
if (throttling) {
more = true;
} else {
- func.apply(context, args);
+ result = func.apply(context, args);
}
whenDone();
throttling = true;
+ return result;
};
- }; |
| Returns a function, that, as long as it continues to be invoked, will not
+ }; |
| Returns a function, that, as long as it continues to be invoked, will not
be triggered. The function will be called after it stops being called for
-N milliseconds. | _.debounce = function(func, wait) {
+N milliseconds. If immediate is passed, trigger the function on the
+leading edge, instead of the trailing. | _.debounce = function(func, wait, immediate) {
var timeout;
return function() {
var context = this, args = arguments;
var later = function() {
timeout = null;
- func.apply(context, args);
+ if (!immediate) func.apply(context, args);
};
+ if (immediate && !timeout) func.apply(context, args);
clearTimeout(timeout);
timeout = setTimeout(later, wait);
};
- }; |
| Returns a function that will be executed at most one time, no matter how
+ }; |
| Returns a function that will be executed at most one time, no matter how
often you call it. Useful for lazy initialization. | _.once = function(func) {
var ran = false, memo;
return function() {
@@ -399,14 +401,14 @@
ran = true;
return memo = func.apply(this, arguments);
};
- }; |
| Returns the first function passed as an argument to the second,
+ }; |
| Returns the first function passed as an argument to the second,
allowing you to adjust arguments, run code before and after, and
conditionally execute the original function. | _.wrap = function(func, wrapper) {
return function() {
var args = [func].concat(slice.call(arguments, 0));
return wrapper.apply(this, args);
};
- }; |
| Returns a function that is the composition of a list of functions, each
+ }; |
| Returns a function that is the composition of a list of functions, each
consuming the return value of the function that follows. | _.compose = function() {
var funcs = arguments;
return function() {
@@ -416,196 +418,231 @@
}
return args[0];
};
- }; |
| Returns a function that will only be executed after being called N times. | _.after = function(times, func) {
+ }; |
| Returns a function that will only be executed after being called N times. | _.after = function(times, func) {
if (times <= 0) return func();
return function() {
if (--times < 1) { return func.apply(this, arguments); }
};
- }; |
Object Functions | |
| Retrieve the names of an object's properties.
+ }; |
Object Functions | |
| Retrieve the names of an object's properties.
Delegates to ECMAScript 5's native Object.keys | _.keys = nativeKeys || function(obj) {
if (obj !== Object(obj)) throw new TypeError('Invalid object');
var keys = [];
for (var key in obj) if (_.has(obj, key)) keys[keys.length] = key;
return keys;
- }; |
| Retrieve the values of an object's properties. | _.values = function(obj) {
+ }; |
| Retrieve the values of an object's properties. | _.values = function(obj) {
return _.map(obj, _.identity);
- }; |
| Return a sorted list of the function names available on the object.
+ }; |
| Return a sorted list of the function names available on the object.
Aliased as methods | _.functions = _.methods = function(obj) {
var names = [];
for (var key in obj) {
if (_.isFunction(obj[key])) names.push(key);
}
return names.sort();
- }; |
| Extend a given object with all the properties in passed-in object(s). | _.extend = function(obj) {
+ }; |
| Extend a given object with all the properties in passed-in object(s). | _.extend = function(obj) {
each(slice.call(arguments, 1), function(source) {
for (var prop in source) {
obj[prop] = source[prop];
}
});
return obj;
- }; |
| Fill in a given object with default properties. | _.defaults = function(obj) {
+ }; |
| Return a copy of the object only containing the whitelisted properties. | _.pick = function(obj) {
+ var result = {};
+ each(_.flatten(slice.call(arguments, 1)), function(key) {
+ if (key in obj) result[key] = obj[key];
+ });
+ return result;
+ }; |
| Fill in a given object with default properties. | _.defaults = function(obj) {
each(slice.call(arguments, 1), function(source) {
for (var prop in source) {
if (obj[prop] == null) obj[prop] = source[prop];
}
});
return obj;
- }; |
| Create a (shallow-cloned) duplicate of an object. | _.clone = function(obj) {
+ }; |
| Create a (shallow-cloned) duplicate of an object. | _.clone = function(obj) {
if (!_.isObject(obj)) return obj;
return _.isArray(obj) ? obj.slice() : _.extend({}, obj);
- }; |
| Invokes interceptor with the obj, and then returns obj.
+ }; |
| Invokes interceptor with the obj, and then returns obj.
The primary purpose of this method is to "tap into" a method chain, in
order to perform operations on intermediate results within the chain. | _.tap = function(obj, interceptor) {
interceptor(obj);
return obj;
- }; |
| Internal recursive comparison function. | function eq(a, b, stack) { |
| Identical objects are equal. 0 === -0, but they aren't identical.
-See the Harmony egal proposal: http://wiki.ecmascript.org/doku.php?id=harmony:egal. | if (a === b) return a !== 0 || 1 / a == 1 / b; |
| A strict comparison is necessary because null == undefined. | if (a == null || b == null) return a === b; |
| Unwrap any wrapped objects. | if (a._chain) a = a._wrapped;
- if (b._chain) b = b._wrapped; |
| Invoke a custom isEqual method if one is provided. | if (a.isEqual && _.isFunction(a.isEqual)) return a.isEqual(b);
- if (b.isEqual && _.isFunction(b.isEqual)) return b.isEqual(a); |
| Compare [[Class]] names. | var className = toString.call(a);
+ }; |
| Internal recursive comparison function. | function eq(a, b, stack) { |
| Identical objects are equal. 0 === -0, but they aren't identical.
+See the Harmony egal proposal: http://wiki.ecmascript.org/doku.php?id=harmony:egal. | if (a === b) return a !== 0 || 1 / a == 1 / b; |
| A strict comparison is necessary because null == undefined. | if (a == null || b == null) return a === b; |
| Unwrap any wrapped objects. | if (a._chain) a = a._wrapped;
+ if (b._chain) b = b._wrapped; |
| Invoke a custom isEqual method if one is provided. | if (a.isEqual && _.isFunction(a.isEqual)) return a.isEqual(b);
+ if (b.isEqual && _.isFunction(b.isEqual)) return b.isEqual(a); |
| Compare [[Class]] names. | var className = toString.call(a);
if (className != toString.call(b)) return false;
- switch (className) { |
| Strings, numbers, dates, and booleans are compared by value. | |
| Primitives and their corresponding object wrappers are equivalent; thus, "5" is
+ switch (className) { |
| Strings, numbers, dates, and booleans are compared by value. | |
| Primitives and their corresponding object wrappers are equivalent; thus, "5" is
equivalent to new String("5"). | return a == String(b);
- case '[object Number]': |
| NaNs are equivalent, but non-reflexive. An egal comparison is performed for
+ case '[object Number]':
|
| NaNs are equivalent, but non-reflexive. An egal comparison is performed for
other numeric values.
| return a != +a ? b != +b : (a == 0 ? 1 / a == 1 / b : a == +b);
case '[object Date]':
- case '[object Boolean]': |
| Coerce dates and booleans to numeric primitive values. Dates are compared by their
+ case '[object Boolean]': |
| Coerce dates and booleans to numeric primitive values. Dates are compared by their
millisecond representations. Note that invalid dates with millisecond representations
-of NaN are not equivalent. | |
| RegExps are compared by their source patterns and flags. | case '[object RegExp]':
+of NaN are not equivalent. | |
| RegExps are compared by their source patterns and flags. | case '[object RegExp]':
return a.source == b.source &&
a.global == b.global &&
a.multiline == b.multiline &&
a.ignoreCase == b.ignoreCase;
}
- if (typeof a != 'object' || typeof b != 'object') return false; |
| Assume equality for cyclic structures. The algorithm for detecting cyclic
+ if (typeof a != 'object' || typeof b != 'object') return false; |
| Assume equality for cyclic structures. The algorithm for detecting cyclic
structures is adapted from ES 5.1 section 15.12.3, abstract operation JO. | var length = stack.length;
- while (length--) { |
| Linear search. Performance is inversely proportional to the number of
+ while (length--) { |
| Linear search. Performance is inversely proportional to the number of
unique nested structures. | if (stack[length] == a) return true;
- } |
| Add the first object to the stack of traversed objects. | stack.push(a);
- var size = 0, result = true; |
| Recursively compare objects and arrays. | if (className == '[object Array]') { |
| Compare array lengths to determine if a deep comparison is necessary. | |
| Add the first object to the stack of traversed objects. | stack.push(a);
+ var size = 0, result = true; |
| Recursively compare objects and arrays. | if (className == '[object Array]') { |
| Compare array lengths to determine if a deep comparison is necessary. | size = a.length;
result = size == b.length;
- if (result) { |
| Deep compare the contents, ignoring non-numeric properties. | |
| Ensure commutative equality for sparse arrays. | if (!(result = size in a == size in b && eq(a[size], b[size], stack))) break;
+ if (result) { |
| Deep compare the contents, ignoring non-numeric properties. | |
| Ensure commutative equality for sparse arrays. | if (!(result = size in a == size in b && eq(a[size], b[size], stack))) break;
}
}
- } else { |
| Objects with different constructors are not equivalent. | if ('constructor' in a != 'constructor' in b || a.constructor != b.constructor) return false; |
| Deep compare objects. | for (var key in a) {
- if (_.has(a, key)) { |
| Count the expected number of properties. | |
| Deep compare each member. | if (!(result = _.has(b, key) && eq(a[key], b[key], stack))) break;
+ } else { |
| Objects with different constructors are not equivalent. | if ('constructor' in a != 'constructor' in b || a.constructor != b.constructor) return false; |
| Deep compare objects. | for (var key in a) {
+ if (_.has(a, key)) { |
| Count the expected number of properties. | |
| Deep compare each member. | if (!(result = _.has(b, key) && eq(a[key], b[key], stack))) break;
}
- } |
| Ensure that both objects contain the same number of properties. | |
| Ensure that both objects contain the same number of properties. | if (result) {
for (key in b) {
if (_.has(b, key) && !(size--)) break;
}
result = !size;
}
- } |
| Remove the first object from the stack of traversed objects. | |
| Remove the first object from the stack of traversed objects. | stack.pop();
return result;
- } |
| Perform a deep comparison to check if two objects are equal. | _.isEqual = function(a, b) {
+ } |
| Perform a deep comparison to check if two objects are equal. | _.isEqual = function(a, b) {
return eq(a, b, []);
- }; |
| Is a given array, string, or object empty?
+ }; |
| Is a given array, string, or object empty?
An "empty" object has no enumerable own-properties. | _.isEmpty = function(obj) {
+ if (obj == null) return true;
if (_.isArray(obj) || _.isString(obj)) return obj.length === 0;
for (var key in obj) if (_.has(obj, key)) return false;
return true;
- }; |
| Is a given value a DOM element? | _.isElement = function(obj) {
+ }; |
| Is a given value a DOM element? | _.isElement = function(obj) {
return !!(obj && obj.nodeType == 1);
- }; |
| Is a given value an array?
+ }; |
| Is a given value an array?
Delegates to ECMA5's native Array.isArray | _.isArray = nativeIsArray || function(obj) {
return toString.call(obj) == '[object Array]';
- }; |
| Is a given variable an object? | _.isObject = function(obj) {
+ }; |
| Is a given variable an object? | _.isObject = function(obj) {
return obj === Object(obj);
- }; |
| Is a given variable an arguments object? | _.isArguments = function(obj) {
+ }; |
| Is a given variable an arguments object? | _.isArguments = function(obj) {
return toString.call(obj) == '[object Arguments]';
};
if (!_.isArguments(arguments)) {
_.isArguments = function(obj) {
return !!(obj && _.has(obj, 'callee'));
};
- } |
| Is a given value a function? | _.isFunction = function(obj) {
+ } |
| Is a given value a function? | _.isFunction = function(obj) {
return toString.call(obj) == '[object Function]';
- }; |
| Is a given value a string? | _.isString = function(obj) {
+ }; |
| Is a given value a string? | _.isString = function(obj) {
return toString.call(obj) == '[object String]';
- }; |
| Is a given value a number? | _.isNumber = function(obj) {
+ }; |
| Is a given value a number? | _.isNumber = function(obj) {
return toString.call(obj) == '[object Number]';
- }; |
| Is the given value NaN? | _.isNaN = function(obj) { |
| NaN is the only value for which === is not reflexive.
| |
| Is a given value a boolean? | _.isBoolean = function(obj) {
+ }; |
| Is a given object a finite number? | _.isFinite = function(obj) {
+ return _.isNumber(obj) && isFinite(obj);
+ }; |
| Is the given value NaN? | _.isNaN = function(obj) { |
| NaN is the only value for which === is not reflexive.
| |
| Is a given value a boolean? | _.isBoolean = function(obj) {
return obj === true || obj === false || toString.call(obj) == '[object Boolean]';
- }; |
| Is a given value a date? | _.isDate = function(obj) {
+ }; |
| Is a given value a date? | _.isDate = function(obj) {
return toString.call(obj) == '[object Date]';
- }; |
| Is the given value a regular expression? | _.isRegExp = function(obj) {
+ }; |
| Is the given value a regular expression? | _.isRegExp = function(obj) {
return toString.call(obj) == '[object RegExp]';
- }; |
| Is a given value equal to null? | _.isNull = function(obj) {
+ }; |
| Is a given value equal to null? | _.isNull = function(obj) {
return obj === null;
- }; |
| Is a given variable undefined? | _.isUndefined = function(obj) {
+ }; |
| Is a given variable undefined? | _.isUndefined = function(obj) {
return obj === void 0;
- }; |
| Has own property? | _.has = function(obj, key) {
+ }; |
| Has own property? | _.has = function(obj, key) {
return hasOwnProperty.call(obj, key);
- }; |
Utility Functions | |
| Run Underscore.js in noConflict mode, returning the _ variable to its
+ }; |
Utility Functions | |
| Run Underscore.js in noConflict mode, returning the _ variable to its
previous owner. Returns a reference to the Underscore object. | _.noConflict = function() {
root._ = previousUnderscore;
return this;
- }; |
| Keep the identity function around for default iterators. | _.identity = function(value) {
+ }; |
| Keep the identity function around for default iterators. | _.identity = function(value) {
return value;
- }; |
| Run a function n times. | _.times = function (n, iterator, context) {
+ }; |
| Run a function n times. | _.times = function (n, iterator, context) {
for (var i = 0; i < n; i++) iterator.call(context, i);
- }; |
| Escape a string for HTML interpolation. | _.escape = function(string) {
+ }; |
| Escape a string for HTML interpolation. | _.escape = function(string) {
return (''+string).replace(/&/g, '&').replace(/</g, '<').replace(/>/g, '>').replace(/"/g, '"').replace(/'/g, ''').replace(/\//g,'/');
- }; |
| Add your own custom functions to the Underscore object, ensuring that
+ }; |
| If the value of the named property is a function then invoke it;
+otherwise, return it. | _.result = function(object, property) {
+ if (object == null) return null;
+ var value = object[property];
+ return _.isFunction(value) ? value.call(object) : value;
+ }; |
| Add your own custom functions to the Underscore object, ensuring that
they're correctly added to the OOP wrapper as well. | _.mixin = function(obj) {
each(_.functions(obj), function(name){
addToWrapper(name, _[name] = obj[name]);
});
- }; |
| Generate a unique integer id (unique within the entire client session).
+ }; |
| Generate a unique integer id (unique within the entire client session).
Useful for temporary DOM ids. | var idCounter = 0;
_.uniqueId = function(prefix) {
var id = idCounter++;
return prefix ? prefix + id : id;
- }; |
| By default, Underscore uses ERB-style template delimiters, change the
+ }; |
| By default, Underscore uses ERB-style template delimiters, change the
following template settings to use alternative delimiters. | _.templateSettings = {
evaluate : /<%([\s\S]+?)%>/g,
interpolate : /<%=([\s\S]+?)%>/g,
escape : /<%-([\s\S]+?)%>/g
- }; |
| When customizing templateSettings, if you don't want to define an
+ }; |
| When customizing templateSettings, if you don't want to define an
interpolation, evaluation or escaping regex, we need one that is
-guaranteed not to match. | |
| Within an interpolation, evaluation, or escaping, remove HTML escaping
+guaranteed not to match. | |
| Certain characters need to be escaped so that they can be put into a
+string literal. | var escapes = {
+ '\\': '\\',
+ "'": "'",
+ 'r': '\r',
+ 'n': '\n',
+ 't': '\t',
+ 'u2028': '\u2028',
+ 'u2029': '\u2029'
+ };
+
+ for (var p in escapes) escapes[escapes[p]] = p;
+ var escaper = /\\|'|\r|\n|\t|\u2028|\u2029/g;
+ var unescaper = /\\(\\|'|r|n|t|u2028|u2029)/g; |
| Within an interpolation, evaluation, or escaping, remove HTML escaping
that had been previously added. | var unescape = function(code) {
- return code.replace(/\\\\/g, '\\').replace(/\\'/g, "'");
- }; |
| JavaScript micro-templating, similar to John Resig's implementation.
+ return code.replace(unescaper, function(match, escape) {
+ return escapes[escape];
+ });
+ }; |
| JavaScript micro-templating, similar to John Resig's implementation.
Underscore templating handles arbitrary delimiters, preserves whitespace,
-and correctly escapes quotes within interpolated code. | _.template = function(str, data) {
- var c = _.templateSettings;
- var tmpl = 'var __p=[],print=function(){__p.push.apply(__p,arguments);};' +
- 'with(obj||{}){__p.push(\'' +
- str.replace(/\\/g, '\\\\')
- .replace(/'/g, "\\'")
- .replace(c.escape || noMatch, function(match, code) {
- return "',_.escape(" + unescape(code) + "),'";
- })
- .replace(c.interpolate || noMatch, function(match, code) {
- return "'," + unescape(code) + ",'";
- })
- .replace(c.evaluate || noMatch, function(match, code) {
- return "');" + unescape(code).replace(/[\r\n\t]/g, ' ') + ";__p.push('";
- })
- .replace(/\r/g, '\\r')
- .replace(/\n/g, '\\n')
- .replace(/\t/g, '\\t')
- + "');}return __p.join('');";
- var func = new Function('obj', '_', tmpl);
- if (data) return func(data, _);
- return function(data) {
- return func.call(this, data, _);
- };
- }; |
| Add a "chain" function, which will delegate to the wrapper. | _.chain = function(obj) {
+and correctly escapes quotes within interpolated code. | _.template = function(text, data, settings) {
+ settings = _.extend(_.templateSettings, settings); |
| Compile the template source, taking care to escape characters that
+cannot be included in a string literal and then unescape them in code
+blocks. | var source = "__p+='" + text
+ .replace(escaper, function(match) {
+ return '\\' + escapes[match];
+ })
+ .replace(settings.escape || noMatch, function(match, code) {
+ return "'+\n_.escape(" + unescape(code) + ")+\n'";
+ })
+ .replace(settings.interpolate || noMatch, function(match, code) {
+ return "'+\n(" + unescape(code) + ")+\n'";
+ })
+ .replace(settings.evaluate || noMatch, function(match, code) {
+ return "';\n" + unescape(code) + "\n;__p+='";
+ }) + "';\n"; |
| If a variable is not specified, place data values in local scope. | if (!settings.variable) source = 'with(obj||{}){\n' + source + '}\n';
+
+ source = "var __p='';" +
+ "var print=function(){__p+=Array.prototype.join.call(arguments, '')};\n" +
+ source + "return __p;\n";
+
+ var render = new Function(settings.variable || 'obj', '_', source);
+ if (data) return render(data, _);
+ var template = function(data) {
+ return render.call(this, data, _);
+ }; |
| Provide the compiled function source as a convenience for build time
+precompilation. | template.source = 'function(' + (settings.variable || 'obj') + '){\n' +
+ source + '}';
+
+ return template;
+ }; |
| Add a "chain" function, which will delegate to the wrapper. | _.chain = function(obj) {
return _(obj).chain();
- }; |
The OOP Wrapper | |
| If Underscore is called as a function, it returns a wrapped object that
+ }; |
The OOP Wrapper | |
| If Underscore is called as a function, it returns a wrapped object that
can be used OO-style. This wrapper holds altered versions of all the
-underscore functions. Wrapped objects may be chained. | var wrapper = function(obj) { this._wrapped = obj; }; |
| Expose wrapper.prototype as _.prototype | _.prototype = wrapper.prototype; |
| Helper function to continue chaining intermediate results. | var result = function(obj, chain) {
+underscore functions. Wrapped objects may be chained. | var wrapper = function(obj) { this._wrapped = obj; }; |
| Expose wrapper.prototype as _.prototype | _.prototype = wrapper.prototype; |
| Helper function to continue chaining intermediate results. | var result = function(obj, chain) {
return chain ? _(obj).chain() : obj;
- }; |
| A method to easily add functions to the OOP wrapper. | var addToWrapper = function(name, func) {
+ }; |
| A method to easily add functions to the OOP wrapper. | var addToWrapper = function(name, func) {
wrapper.prototype[name] = function() {
var args = slice.call(arguments);
unshift.call(args, this._wrapped);
return result(func.apply(_, args), this._chain);
};
- }; |
| Add all of the Underscore functions to the wrapper object. | |
| Add all mutator Array functions to the wrapper. | each(['pop', 'push', 'reverse', 'shift', 'sort', 'splice', 'unshift'], function(name) {
+ }; |
| Add all of the Underscore functions to the wrapper object. | |
| Add all mutator Array functions to the wrapper. | each(['pop', 'push', 'reverse', 'shift', 'sort', 'splice', 'unshift'], function(name) {
var method = ArrayProto[name];
wrapper.prototype[name] = function() {
var wrapped = this._wrapped;
@@ -614,15 +651,15 @@
if ((name == 'shift' || name == 'splice') && length === 0) delete wrapped[0];
return result(wrapped, this._chain);
};
- }); |
| Add all accessor Array functions to the wrapper. | each(['concat', 'join', 'slice'], function(name) {
+ }); |
| Add all accessor Array functions to the wrapper. | each(['concat', 'join', 'slice'], function(name) {
var method = ArrayProto[name];
wrapper.prototype[name] = function() {
return result(method.apply(this._wrapped, arguments), this._chain);
};
- }); |
| Start chaining a wrapped Underscore object. | wrapper.prototype.chain = function() {
+ }); |
| Start chaining a wrapped Underscore object. | wrapper.prototype.chain = function() {
this._chain = true;
return this;
- }; |
| Extracts the result from a wrapped and chained object. | wrapper.prototype.value = function() {
+ }; |
| Extracts the result from a wrapped and chained object. | wrapper.prototype.value = function() {
return this._wrapped;
};
diff --git a/index.html b/index.html
index a60c8d33e..c00b98a8d 100644
--- a/index.html
+++ b/index.html
@@ -136,7 +136,7 @@
|