https://ramda.cn/docs/#cond

    逻辑判断

    1. const fn = R.cond([
    2.   [R.equals(0),   R.always('water freezes at 0°C')],
    3.   [R.equals(100), R.always('water boils at 100°C')],
    4.   [R.T,           temp => 'nothing special happens at ' + temp + '°C']
    5. ]);
    6. fn(0); //=> 'water freezes at 0°C'
    7. fn(50); //=> 'nothing special happens at 50°C'
    8. fn(100); //=> 'water boils at 100°C'