boolean logic in ruby 'true and false == true'

问题

> test = false and true
=> false
> test
=> false
> test = true and false #this is the point I don't understand!
=> false
> test
=> true

Why does ruby behave in this way and how would I use it correctly to not run into this problem?

回答1:

Precedence. test = true and false means this:

(test = true) and false  

not this:

test = (true and false)

Use parentheses as above, or && instead of and, if you want the assignment to come last:

test = true && false

来源：https://stackoverflow.com/questions/10249164/boolean-logic-in-ruby-true-and-false-true