ngrepeat

ng-repeat is a directive in AngularJS (1.x) that renders a template block for each item in a collection. It creates a new scope for each item, allowing the item to be bound to a local variable inside the repeated markup.

Basic usage is ng-repeat="item in items", where items is an array. Inside the template, item refers to the current element. AngularJS also exposes iteration properties such as $index, $first, $last, $middle, $odd, and $even. ng-repeat can also iterate over objects with ng-repeat="(key, value) in myObject". For complex layouts, ng-repeat-start and ng-repeat-end can be used to repeat a block that spans multiple elements.

Advanced options include track by, which improves performance when the collection changes. For example, ng-repeat="item in items track by item.id" uses a stable identifier to minimize DOM updates. Filters and pipelines can be applied within the expression, such as ng-repeat="item in items | orderBy: predicate | limitTo: 10".

Performance considerations arise because ng-repeat creates a child scope for each item, which can impact digest cycles on large lists. To mitigate this, developers often use track by, limitTo, pagination, or virtualization where appropriate. ng-repeat is specific to AngularJS 1.x and is not used in Angular (2+), where the equivalent feature is the *ngFor directive.

Common use cases include rendering lists, tables, or select options, and generally any repeated markup bound to an array or object within an AngularJS template.