You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
1004 B
1004 B
Cursors
Cursors allow you to hold a reference to a path in a nested immutable data
structure, allowing you to pass smaller sections of a larger nested
collection to portions of your application while maintaining a central point
aware of changes to the entire data structure: an onChange
function which is
called whenever a cursor or sub-cursor calls update
.
This is particularly useful when used in conjuction with component-based UI libraries like React or to simulate "state" throughout an application while maintaining a single flow of logic.
var Immutable = require('immutable');
var Cursor = require('immutable/contrib/cursor');
var data = Immutable.fromJS({ a: { b: { c: 1 } } });
var cursor = Cursor.from(data, ['a', 'b'], newData => {
data = newData;
});
// ... elsewhere ...
cursor.get('c'); // 1
cursor = cursor.update('c', x => x + 1);
cursor.get('c'); // 2
// ... back to data ...
data.getIn(['a', 'b', 'c']); // 2