and replacing it with a new default value.
SDL uses a union headed by an enum for event polling (checking key presses, mouse movement, closing the window). I don't think would be possible to properly express tagged unions in APL without massive pain. Instead, I wrote functions that checked if keys were pressed, the mouse was moved and functions that returned relevant data if these events did happen.
，这一点在搜狗输入法中也有详细论述
Раскрыта судьба не нашедшего покупателей особняка Лободы в России20:51
Дмитрий Воронин