`

perl中的and or

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perl的操作符 &&,||除了具有静态语言如java的特性外,其操作符两端还可以是任意表达式

例子1:

 sub a{
 	print "a\n";
 }
 sub b{
 	print "b\n";
 }
a||b;

 以上输出为

可以看出若无返回值则当做返回true处理

 

例子2:

 sub a{
 	print "a\n";
                return 0;
 }
 sub b{
 	print "b\n";
 }
a||b;

 

输出为

a

b

 

对于&&操作符,则有点类似,在此不举例了

 

通过使用&&,||,可以很灵活的执行一些表达式组合

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