perl的模块组织方式

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如何使用自己写的私人模块

模块通俗来讲，就是一堆函数的集合。

Personally I prefer to keep my modules (those that I write for myself or for systems I can control) in a certain directory, and also to place them in a subdirectory. As in:

/www/modules/MyMods/Foo.pm
/www/modules/MyMods/Bar.pm

And then where I use them:

use lib qw(/www/modules);useMyMods::Foo; 

useMyMods::Bar;

As reported by "perldoc -f use":

It is exactly equivalent to
BEGIN { require Module; import Module LIST; }
except that Module must be a bareword.

Putting that another way, "use" is equivalent to:

  • running at compile time,
  • converting the package name to a file name,
  • require-ing that file name, and
  • import-ing that package.

So, instead of calling use, you can call require and import inside a BEGIN block:

BEGIN{require'../EPMS.pm';
  EPMS->import();}

And of course, if your module don't actually do any symbol exporting or other initialization when you call import, you can leave that line out:

BEGIN{require'../EPMS.pm';}
比如我的一个模块如下，命名为my_stat.pm：
package my_stat;
sub mean{
my $sum=0;
$sum+=$_ foreach @_;
$sum/($#_+1);
}
#print &mean(1..10),"\n";
sub stddev{
$avg=&mean(@_);
#print "$avg\n";
my $sum=0;
$sum+=($_-$avg)**2 foreach @_;
sqrt($sum/($#_));
#It will be different if you use $#_+1;
#sqrt($sum/($#_+1));
}
#print &stddev(1..10),"\n";
1;
里面有我定义好的两个函数 mean 和 stddev , 那么我就可以在我的其它perl程序里面直接引用这个模块，从而使用我的两个自定义函数。
use lib "./";  #取决于你把自定义模块my_stat.pm放在哪个目录
use my_stat;
print my_stat::stddev(1..10),"\n";

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