Creates a function that invokes func with the arguments of the created function. If func is a property name, the created function returns the property value for a given element. If func is an array or object, the created function returns true for elements that contain the equivalent source properties, otherwise it returns false. Fetch the default set of models for this collection from the server, setting them on the collection when they arrive. The options hash takes success and error callbacks which will both be passed as arguments. When the model data returns from the server, it uses setto merge the fetched models, unless you pass , in which case the collection will be reset.
Delegates to Backbone.syncunder the covers for custom persistence strategies and returns a jqXHR. The server handler for fetch requests should return a JSON array of models. When returning a JSON response, send down the attributes of the model that have been changed by the server, and need to be updated on the client. When responding to a "read" request from a collection (Collection#fetch), send down an array of model attribute objects. The exact meaning of this header field depends on the implementation of the origin server and the nature of the original resource. For files, it may be just the file system last-modified time.
For entities with dynamically included parts, it may be the most recent of the set of last-modify times for its component parts. For database gateways, it may be the last-update time stamp of the record. For virtual objects, it may be the last time the internal state changed. Parse is called by Backbone whenever a collection's models are returned by the server, in fetch.
The function is passed the raw response object, and should return the array of model attributes to be addedto the collection. The default implementation is a no-op, simply passing through the JSON response. Override this if you need to work with a preexisting API, or better namespace your responses. By default save checks validate before setting any attributes but you may also tell set to validate the new attributes by passing as an option. If called with no arguments, first emits the first value of the source Observable, then completes.
If called with a predicate function, firstemits the first value of the source that matches the specified condition. It may also take a resultSelector function to produce the output value from the input value, and a defaultValue to emit in case the source completes before it is able to emit a valid value. Throws an error if defaultValuewas not provided and a matching element is not found.
Expand will re-emit on the output Observable every source value. Then, each output value is given to theproject function which returns an inner Observable to be merged on the output Observable. Those output values resulting from the projection are also given to the project function to produce new output values.
Count transforms an Observable that emits values into an Observable that emits a single value that represents the number of values emitted by the source Observable. If the source Observable terminates with an error, countwill pass this error notification along without emitting a value first. If the source Observable does not terminate at all, count will neither emit a value nor terminate. This operator takes an optional predicate function as argument, in which case the output emission will represent the number of source values that matched true with the predicate. WhenfromEvent is used with event target of that type, you can provide this values as third parameter as well.
Optionally forkJoin accepts project function, that will be called with values which normally would land in emitted array. Whatever is returned by project function, will appear in output Observable instead. This means that default project can be thought of as a function that takes all its arguments and puts them into an array. Note that project function will be called only when output Observable is supposed to emit a result. Most of the loops you'll write in CoffeeScript will be comprehensions over arrays, objects, and ranges. Comprehensions replace for loops, with optional guard clauses and the value of the current array index.
Unlike for loops, array comprehensions are expressions, and can be returned and assigned. The Expires entity-header field gives the date/time after which the response is considered stale. A stale cache entry may not normally be returned by a cache unless it is first validated with the origin server .
See section 13.2 for further discussion of the expiration model. Returns an Observable that emits items based on applying a function that you supply to each item emitted by the source Observable, where that function returns an (so-called "inner") Observable. Each time it observes one of these inner Observables, the output Observable begins emitting the items emitted by that inner Observable. When a new inner Observable is emitted, switchMapstops emitting items from the earlier-emitted inner Observable and begins emitting items from the new one. It continues to behave like this for subsequent inner Observables. Note that project does not take as argument that array of values, but values themselves.
That means default project can be imagined as function that takes all its arguments and puts them into an array. Added an _.defaults function, for use merging together JS objects representing default options. Added an _.once function, for manufacturing functions that should only ever execute a single time.
_.bind now delegates to the native ES5 version, where available. _.keys now throws an error when used on non-Object values, as in ES5. For strings and array-like objects _.isEmpty checks if the length property is 0. For other objects, it returns true if the object has no enumerable own-properties.
Note that primitive numbers, booleans and symbols are always empty by this definition. Memoizes a given function by caching the computed result. If passed an optional hashFunction, it will be used to compute the hash key for storing the result, based on the arguments to the original function. The default hashFunction just uses the first argument to the memoized function as the key.
The cache of memoized values is available as the cacheproperty on the returned function. You can use either numeric or string expressions as arguments for comparison functions. (String constants must be enclosed in single or double quotes.) The expressions can be literals or values fetched by a query. Comparison functions are most often used as filtering conditions in WHERE clauses, but they can be used in other clauses.
It also allows obsolete or mistyped links to be traced for maintenance. The Referer field MUST NOT be sent if the Request-URI was obtained from a source that does not have its own URI, such as input from the user keyboard. If multiple encodings have been applied to an entity, the content codings MUST be listed in the order in which they were applied. Additional information about the encoding parameters MAY be provided by other entity-header fields not defined by this specification. Perhaps the single most common JavaScript "gotcha" is the fact that when you pass a function as a callback, its value for this is lost. View events are automatically bound to the view's context for you.
You may also find it helpful to use _.bind and _.bindAllfrom Underscore.js. Convenience to create a new instance of a model within a collection. Equivalent to instantiating a model with a hash of attributes, saving the model to the server, and adding the model to the set after being successfully created. If client-side validation failed, the model will be unsaved, with validation errors.
In order for this to work, you should set the model property of the collection. The create method can accept either an attributes hash and options to be passed down during model instantiation or an existing, unsaved model object. Adding and removing models one at a time is all well and good, but sometimes you have so many models to change that you'd rather just update the collection in bulk. Use reset to replace a collection with a new list of models , triggering a single "reset" event on completion, and without triggering any add or remove events on any models. For convenience, within a "reset" event, the list of any previous models is available as options.previousModels. Add a model to the collection, firing an "add"event for each model, and an "update" event afterwards.
If a model property is defined, you may also pass raw attributes objects and options, and have them be vivified as instances of the model using the provided options. Pass to splice the model into the collection at the specified index. Parse is called whenever a model's data is returned by the server, in fetch, and save. The function is passed the raw response object, and should return the attributes hash to be set on the model. The normalization rules are written in a specific syntax, allowing you to create rules to affect specific changes to records.
For example, you can edit or delete fields, and you can also do that conditionally, based on some other condition that takes place or doesn't in the bibliographic record. The return or result "parameters" of a Go function can be given names and used as regular variables, just like the incoming parameters. When it projects a source value to an Observable, the output Observable begins emitting the items emitted by that projected Observable. However, exhaustMap ignores every new projected Observable if the previous projected Observable has not yet completed. Once that one completes, it will accept and flatten the next projected Observable and repeat this process. CombineLatest combines the values from this Observable with values from Observables passed as arguments.
Note that if event target calls registered function with more than one argument, second and following arguments will not appear in resulting stream. In order to get access to them, you can pass to fromEvent optional project function, which will be called with all arguments passed to event handler. Output Observable will then emit value returned by project function, instead of the usual value. Optionally, a selector function can be passed to bindObservable. The selector function takes the same arguments as the callback and returns the value that will be emitted by the Observable.
Even though by default multiple arguments passed to callback appear in the stream as an array the selector function will be called with arguments directly, just as the callback would. This means you can imagine the default selector as a function that aggregates all its arguments into an array, or simply returns first argument if there is only one. The output of bindCallback is a function that takes the same parameters as func, except the last one . When the output function is called with arguments it will return an Observable.
If function funccalls its callback with one argument the Observable will emit that value. If on the other hand the callback is called with multiple values the resulting Observable will emit an array with said values as arguments. Assigns own and inherited enumerable string keyed properties of source objects to the destination object for all destination properties that resolve to undefined. Once a property is set, additional values of the same property are ignored. _.bindAll now takes the context object as its first parameter.
If no method names are passed, all of the context object's methods are bound to it, enabling chaining and easier binding. _.functions now takes a single argument and returns the names of its Function properties. Added _.isRegExp so that isEqual can now test for RegExp equality. All of the "is" functions have been shrunk down into a single definition. Each window function requires an OVER clause that specifies the window top and bottom. The three components of the OVERclause provide additional control over the window.
Partitioning enables you to divide the input data into logical groups that have a common characteristic. Ordering enables you to order the results within a partition. Framing enables you to create a sliding window frame within a partition that moves relative to the current row. You can configure the size of the moving window frame based on a number of rows or a range of values, such as a time interval.
The WHERE clause, sometimes called the predicate, filters records produced by the FROM clause using a boolean expression. Multiple conditions can be joined by boolean AND and OR clauses, optionally surrounded by parentheses—()— to group them. CoffeeScript loops no longer try to preserve block scope when functions are being generated within the loop body.
Instead, you can use the do keyword to create a convenient closure wrapper. Added a --nodejs flag for passing through options directly to the node executable. Better behavior around the use of pure statements within expressions. Fixed inclusive slicing through -1, for all browsers, and splicing with arbitrary expressions as endpoints. A cache MAY assume that the same selection will be made for future requests with the same values for the listed field names, for the duration of time for which the response is fresh.
If multiple encodings have been applied to an entity, the transfer- codings MUST be listed in the order in which they were applied. When the no-cache directive is present in a request message, an application SHOULD forward the request toward the origin server even if it has a cached copy of what is being requested. This pragma directive has the same semantics as the no-cache cache-directive (see section 14.9) and is defined here for backward compatibility with HTTP/1.0.
Clients SHOULD include both header fields when a no-cache request is sent to a server not known to be HTTP/1.1 compliant. That is, if no entity tags match, then the server MUST NOT return a 304 response. When a directive appears without any 1#field-name parameter, the directive applies to the entire request or response. When such a directive appears with a 1#field-name parameter, it applies only to the named field or fields, and not to the rest of the request or response. This mechanism supports extensibility; implementations of future versions of the HTTP protocol might apply these directives to header fields not defined in HTTP/1.1. Each model can be a Model instance, an id string or a JS object, any value acceptable as the id argument of collection.get.
Fires a "remove" event for each model, and a single "update" event afterwards, unless is passed. The model's index before removal is available to listeners as options.index. Override this property to specify the model class that the collection contains. If defined, you can pass raw attributes objects and options to add, create, and reset, and the attributes will be converted into a model of the proper type using the provided options, if any. Merges the model's state with attributes fetched from the server by delegating to Backbone.sync. Useful if the model has never been populated with data, or if you'd like to ensure that you have the latest server state.
Triggers a "change" event if the server's state differs from the current attributes. Fetch accepts success and error callbacks in the options hash, which are both passed as arguments. A Model manages an internal table of data attributes, and triggers "change" events when any of its data is modified. Models handle syncing data with a persistence layer — usually a REST API with a backing database. Design your models as the atomic reusable objects containing all of the helpful functions for manipulating their particular bit of data.
