public override DisIntervalEnvironment <Variable, Expression> TestTrueGeqZero(Expression exp)
        {
            var newConstraints = IntervalInference.InferConstraints_GeqZero(exp, this.ExpressionManager.Decoder, this);

            foreach (var pair in newConstraints)
            {
                this[pair.One] = pair.Two;
            }

            return(this);
        }