Eager Load deep recursion problem

you have an infinite loop A loads B which loads C which loads A.

yes i know... but i'd like to stop it - I NEED auto eager loading within my project, but I also need some ideas to stop this stuff

Hmm, hard to say for sure since you are providing an abstract example. But you can Lazy Eager Load the relationships at the point they are being used instead of globally like you are in the example.

Lazy Eager Loading means you would get your collection of A, and then where that is used, load B and C after you have already retrieved the collection of A. It's not ideal, but it should prevent the issue you are having.

well... there is one solution, but it is not ideal one.

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class A extends Model
{
//    protected $with = ['B'];  
    
    public function B() {
        return $this->belongsTo('App\B');
    }
}

class B extends Model
{
    protected $with = ['C'];
    
    public function C() {
        return $this->belongsTo('App\C');
    }
}

class C extends Model
{
    protected $with = ['A'];
    
    public function A() {
        return $this->belongsTo('App\A');
    }
}


dd(\App\A::with('B')->first());

I would rather rethink your app logic

There is a without() method (tested on Laravel 5.4) https://laravel.com/api/5.4/Illuminate/Database/Eloquent/Builder.html#method_without

Placing without() on both sides of a relationship worked.

Example on 2-way relationship: https://stackoverflow.com/a/52880179/3553367

I have not tested on this 3-way relationship but below is an example

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class A extends Model
{
    protected $with = ['B'];
    
    public function B() {
        return $this->belongsTo('App\B')->without('A');
    }
}

class B extends Model
{
    protected $with = ['C'];
    
    public function C() {
        return $this->belongsTo('App\C')->without('B');
    }
}

class C extends Model
{
    protected $with = ['A'];
    
    public function A() {
        return $this->belongsTo('App\A')->without('C);
    }
}