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}}
Just before the helper is invoked two useful variables are defined:
templateContextThe current context that variables are fetched from. This is likely a controller.typeOfTemplateContextA string describing what the templateContext is.
For example, if you are wondering why a specific variable isn't displaying in
your template, you could use the {{debugger}} helper. When the breakpoint is
hit, you can use the templateContext in your console to lookup properties:
> templateContext.get('name')
"Bruce Lee"