Usage of use base in Perl

The use base is used to describe the "base class" in Object-Oriented Programming. To put it bluntly,

Use base somemodule;
It is equivalent to the combination of the following two sentences:

Begin {
Use somemodule ();
Push @ Isa, QW (somemodule );
}
You can also use two or more modules of base at the same time, for example:

Use base QW (FOO bar );
It is equivalent:

Begin {
Use Foo ();
Use bar ();
Push @ Isa, QW (FOO bar );
}
As for what kind of array @ ISA is, it is totally irrelevant to use base,
@ ISA is a special array. For more information about its meaning, see the description in the big camel.

By the way,

Use Foo ();
And
Use Foo;
Is different,
The latter will automatically call the import function in the foo package, but the former will not.

Use base somemodule;
Ratio
Use somemodule;
More than one sentence
Push @ Isa, QW (somemodule );

 

Reprinted: http://blog.csdn.net/zll01/article/details/4520237