If $userchoice is false (see Table 1), then Perl checks the value of $systemchoice and so on until it gets to the last value, which is always used, whether it's true or not.

如果 $userchoice 为假（请参阅表 1），那么 Perl 就需要检查 $systemchoice 的值，依此类推，直到最后一个值，这个值通常都会被使用，不管它是真还是假。

youdao

Now, less than is just, if you haven't used it before, it's just the operator you'd expect, it's comparing two things and it's going to return either true or false depending on whether the first argument is false less than the second argument.

现在，小于这个符号是，如果你之前没用过它的话，它就是你期望的那个运算符，它会比较两个独享,然后基于第一个参数是不是,小于第二个参数,返回true或者。

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