AffiliateWP - disable affiliate to affiliate referrals

gistfile1.php

<?php

function affwp_custom_disable_affiliate_to_affiliate_referrals( $referral_amount, $affiliate_id, $amount, $reference, $product_id ) {

	// affwp_is_affiliate() will check if the currently logged in user is an affilaite.
	// if they are an affiliate, set the referral amount to 0.00
	if ( affwp_is_affiliate() ) {
		$referral_amount = 0.00;
	}

	return $referral_amount;
}
add_filter( 'affwp_calc_referral_amount', 'affwp_custom_disable_affiliate_to_affiliate_referrals', 10, 5 );