Perl语言入门：第七章习题：输出文件中包含一个大写字母的所有行，不输出一行的内容全是大写的

文件内容：

bash-2.03$ cat file_4_ex_ch7.txt
anonymous attribute demolition grammar rules indices refernces lignA
Align,

ligning.
.
AABB

代码：

     80 print " ----------------------------------exercise_ch7_4-------------------------- ";
     81 while(<>){
     82     if(/[A-Z][a-z]+/){
     83         print $_." " ;
     84     }
     85     if(/[a-z][A-Z]/){
     86         print $_." " ;
     87     }
     88 }
     89 print " ----------------------------------exercise_ch7_4-------------------------- ";

输出：

----------------------------------exercise_ch7_4--------------------------
anonymous attribute demolition grammar rules indices refernces lignA

Align,


----------------------------------exercise_ch7_4--------------------------