ruby的逻辑运算符and与&&

ruby的逻辑运算符and与&&
ruby中,and与&&是有区别的,而且不在“短路”运算上。看例子:
puts true and false
puts (true and false)
puts true && false
puts true & false
////~>
true
false
false
false

翻资料发现ruby1.8.7有这么个说法:
引用

Use &&/|| for boolean expressions, and/or for control flow. (Rule of thumb: If you have to use outer parentheses, you are using the wrong operators.)