Adding Global Keyword?

Sec has asked for the wisdom of the Perl Monks concerning the following question:

I have been trying to use a new global keyword in a script, but have failed so far. My try so far.

package CORE::GLOBAL;
use subs qw(dwim);
sub dwim { print "dwim\n"; }

package test;
dwim();
[download]

But if I try to do that with an pre existing keyword it works fine:

package CORE::GLOBAL;
use subs qw(warn);
sub warn { print "dwim\n"; }

package test;
warn();
[download]

Can anybody help?

Comment on Adding Global Keyword? Select or Download Code

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Re: Adding Global Keyword? by Corion (Patriarch) on Feb 17, 2006 at 15:07 UTC
You don't want to do that. As you've made it clear in the CB that this is out of curiosity only, here is a way to add new "global" functions to everywhere: `package UNIVERSAL; sub AUTOLOAD{print $AUTOLOAD}; package main; Test(); &{'Just another Perl Hacker'}();` [download] You should add some checking that you raise errors for "keywords" you don't know. Also interesting to you might be Shell.pm.	[reply] [d/l]
Re: Adding Global Keyword? by dragonchild (Archbishop) on Feb 17, 2006 at 15:24 UTC
What's wrong with following 50 years of good coding practices and adding a single line to each package that uses your dwim() to explicitly import it? Otherwise, you're creating a maintenance nightmare for the poor schlup who has to read your code in 6 months. Remember, what you think of as a good idea right now will be cursed by the guy who reads it. 90% of the time, that guy will be you. If you want to do something because it's "clever", remember that's code for "stupid". My criteria for good software: Does it work? Can someone else come in, make a change, and be reasonably certain no bugs were introduced?	[reply]
Re^2: Adding Global Keyword? by Sec (Monk) on Feb 17, 2006 at 15:29 UTC
The question came from a friend, who wanted to use it just temporarily for debugging. He didn't want to import his "Debugging module" in every single package. I know that in this case "Module::debug()" works. I looked into this problem out of sheer curiosity. It feels strangely unperlish to me that perl allows me to override existing builtin keywords, but not add my own.	[reply]
Re^3: Adding Global Keyword? by dragonchild (Archbishop) on Feb 17, 2006 at 15:33 UTC
Look into if and conditional compilation using constants. My criteria for good software: Does it work? Can someone else come in, make a change, and be reasonably certain no bugs were introduced?	[reply]
Re^3: Adding Global Keyword? by Anonymous Monk on Feb 18, 2006 at 11:17 UTC
I'd cheat. `sub what::s { ... debug code here... }` [download] Then later, anywhere... `what's($foo); what's($bar);` [download]	[reply] [d/l] [select]