That function is part of Carbon, which is what Eloquent uses for datetime fields.

https://github.com/briannesbitt/Carbon#api-humandiff

Eloquent timestamps are actually converted into instances of Carbon. diffForHumans() is a method from Carbon.

Just to add to the above: if you want your own model properties (database fields) to be converted into Carbon instances, add them to the Model's dates property. I detailed this on laravel-tricks.com:

http://www.laravel-tricks.com/tricks/model-date-mutators-an-easier-way

meigwilym said:

Just to add to the above: if you want your own model properties (database fields) to be converted into Carbon instances, add them to the Model's dates property. I detailed this on laravel-tricks.com:

http://www.laravel-tricks.com/tricks/model-date-mutators-an-easier-way

I didn't know that, thanks.