如何“使用"一个“使用"的多个模块? [英] How to "use" multiple modules with one "use"?

问题描述

我想在所有程序中使用一些软件包和一些编译指示，例如:

I want use some packages and some pragmas in all my programs, like:

use 5.014;
use warnings;
use autodie;
use My::ModuleA::Something;
use ModuleB qw(Func1 Func2);

我不想在每个模块中重复我自己，所以寻找一种方法来制作一个包装，例如My::Common将包含上述软件包的内容以及在我的程序中仅执行以下操作:

I don't want repeat myself in every module, so looking for a way how to make one package e.g. My::Common what will contain the above packages and in my programs do only:

use My::Common;
say Func1("hello"); #say enabled and Func1 imported in the My::Common

如何实现?

读为preldoc -f use和perldoc perlmodlib，所以我想我必须有点"用BEGIN加上require& import来做到这一点，但绝对不知道如何.

The was read preldoc -f use and perldoc perlmodlib so i think I must "somewhat" to do this with BEGIN plus require&import, but absolutely don't know how.

更新:我已经尝试了基本的操作.

UPDATE: I'm already tried the basic things.

使用require-我的prg.pl程序.

With require - my prg.pl program.

require 'mymods.pl';
$var = "hello";
croak "$var\n";

mymods.pl包含

mymods.pl contain

use strict;
use feature 'say';
use Carp qw(carp croak cluck);
1;

不起作用.出现错误:

$ perl prg.pl 
String found where operator expected at prg.pl line 3, near "croak "$var\n""
    (Do you need to predeclare croak?)
syntax error at prg.pl line 3, near "croak "$var\n""
Execution of prg.pl aborted due to compilation errors.

---

带有使用我的":

---

with "use My":

use My;
$var = "hello";
croak "$var\n";

我的My.pm

package My;
use strict;
use feature 'say';
use Carp qw(carp croak cluck);
1;

也不起作用.遇到相同的错误.

DOES NOT WORKS either. Got the same error.

任何可行的主意吗?

推荐答案

我会这样做:

package My::Common;
use 5.14.0;
use strict;
use warnings;
use autodie;
use Carp qw(carp croak cluck);

sub import {
    my $caller = caller;
    feature->import(':5.14');
    # feature->import('say');
    strict->import;
    warnings->import;
    ## autodie->import; # <-- Won't affect the caller side - see my edit.
    {
        no strict 'refs';
        for my $method (qw/carp croak cluck/) {
            *{"$caller\::$method"} = __PACKAGE__->can($method);
        }
    }
}

1;

如果我错了，请纠正我，否则会有更好的方法.

Please correct me if I'm wrong, or there's a better way.

编辑:

对不起，我在使用autodie->import ...

Sorry, I was wrong in using autodie->import...

这应该可以，但是它假定您总是从main包中调用My::Common:

This one should work, but it assumes that you always call My::Common from the main package:

package My::Common;
# ...
sub import {
    # ...
    strict->import;
    warnings->import;
    {
        package main;
        autodie->import;
    }
    # ...
}

因此，当然，向每个脚本中添加use autodie;更加安全和简单:

So, of course, it's much safer and simpler to add a use autodie; to each script:

use My::Common;
use autodie;
# ...

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