Development Helpers
Development Helpers
Handlebars and Ember come with a few helpers that can make developing your templates a bit easier. These helpers make it simple to output variables into your browser's console, or activate the debugger from your templates.
Logging
The {{log}}
helper makes it easy to output variables or expressions in the current rendering context into your browser's console:
{{log 'Name is:' name}}
The {{log}}
helper also accepts primitive types such as strings or numbers.
Adding a breakpoint
The {{debugger}}
helper provides a handlebars equivalent to JavaScript's debugger
keyword. It will halt execution inside the debugger helper and give you the ability to inspect the current rendering context:
{{debugger}}
When using the debugger helper you will have access to a get
function. This function retrieves values available in the context of the template. For example, if you're wondering why a value {{foo}}
isn't rendering as expected within a template, you could place a {{debugger}}
statement and, when the debugger;
breakpoint is hit, you can attempt to retrieve this value:
> get('foo')
get
is also aware of keywords. So in this situation:
{{#each items as |item|}}
{{debugger}}
{{/each}}
You'll be able to get values from the current item:
> get('item.name')
You can also access the context of the view to make sure it is the object that you expect:
> context
© 2020 Yehuda Katz, Tom Dale and Ember.js contributors
Licensed under the MIT License.
https://guides.emberjs.com/v2.18.0/templates/development-helpers