什么时候Ruby中需要do关键字？

例如,以下代码中是否存在do会影响程序的行为吗？

while true do
    puts "Hi"
    break
end

while true
    puts "Hi"
    break
end

解决方法

根据 The Ruby Programming Language书第5.2.1节：

The do keyword in a while or until loop is like the then keyword in an
if statement: it may be omitted altogether as long as a newline (or
semicolon) appears between the loop condition and the loop body.

所以,不,它不会改变行为,它只是可选语法.