@Nullable
        @Override
        public <R, C> R accept(Visitor<R, C> v, @Nullable C context) {
            return expr.accept(v, context);
        }
Common superclass for {@link FactoryExpression} implementations

@param <T>
querydsl-core/src/main/java/com/querydsl/core/types/FactoryExpressionBase.java