Constructor
new Promise(action)
Constructs a new Promise.
Parameters:
Name | Type | Description |
---|---|---|
action |
function | This should be a call back that takes two parameters: a resolve callback and a reject callback. When the operation is successful, the resolve callback should be called with the result value and if there is an error, the reject callback should be called with an error message. |
Methods
(static) all(promises) → {Promise}
Creates a Promise whose resolution is an Array of all the promises' resolution, and whose rejection is
the first error to occur if any.
Parameters:
Name | Type | Description |
---|---|---|
promises |
* | Any iterable such as an Array of Promise objects. |
Returns:
A Promise whose resolution is an Array of all the promises' resolutions.
- Type
- Promise
(static) reject(reason) → {Promise}
Creates a Promise that rejects with a given reason.
Parameters:
Name | Type | Description |
---|---|---|
reason |
* | Any reason |
Returns:
A promise that rejects with the given reason.
- Type
- Promise
(static) resolve(value) → {Promise}
Creates a Promise that is resolved with a given value.
Parameters:
Name | Type | Description |
---|---|---|
value |
* | Any value |
Returns:
A promise that resolves to the given value.
- Type
- Promise
catch(callback) → {Promise}
Adds a callback that is called when the Promise rejects with an error. The callback should take a parameter
that is the reason for the rejection.
Parameters:
Name | Type | Description |
---|---|---|
callback |
function | A callback |
Returns:
This Promise so that calls may be chained.
- Type
- Promise
finally(callback) → {Promise}
Adds a callback to be executed regardless if the Promise is resolved or rejected. The callback does not
receive any parameters.
Parameters:
Name | Type | Description |
---|---|---|
callback |
function | A callback with no parameters. |
Returns:
This Promise
- Type
- Promise
then(onResolve, onRejectedopt) → {Promise}
Adds a callback to be called when the Promise is resolved and an optional callback to handle rejection.
Parameters:
Name | Type | Attributes | Description |
---|---|---|---|
onResolve |
function | A callback that receives the resolved value | |
onRejected |
function |
<optional> |
An optional callback that receives a rejection reason |
Returns:
This Promise so that calls may be chained.
- Type
- Promise