It looks like that your relation $livre->auteur
is not returning any data, it's probably null, which is not an object and then you get the message Trying to get property of non-object
. To be sure you can do:
Route::any('DynEloquent',function()
{
foreach(Livre::with('auteur')->get() as $livre)
{
dd( $livre->auteur );
}
});
You have to check tour relations, if they are really pointed to the correct $tables and your database table, to see if they are correctly filled with proper relational data.