@mvriel i think this is the point of view. here is the error object filled with one message template which is taken by one validator. With this in mind there is the initialization of the validators by adding a constraint. but we want to have is a logic like if validator a is true validator b is obsolete for example. we then need a kind of buildblan like that i tried to implement with an "validator" to roole them all with the property not to have an violation. sure i can make them "stand alone" validators but we just need the logic to avoid calling a validator if another fails. thats why i implemented it that way.