Re: Unexpected effect of -w with undef

You are giving Perl the code w to execute and the filename if (undef() eq undef()) {print "true" }else{ print "false"} as an argument to it. You probably wanted to say -we… Most of perl's switches are order sensitive.

strict catches this, FWIW:

$ perl -Mstrict -ew 'if(undef() eq undef()){print "true"}else{print "f
+alse"}'
Bareword "w" not allowed while "strict subs" in use at -e line 1.
Execution of -e aborted due to compilation errors.
$ perl -Mstrict -we 'if(undef() eq undef()){print "true"}else{print "f
+alse"}'
Use of uninitialized value in string eq at -e line 1.
Use of uninitialized value in string eq at -e line 1.
true
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Makeshifts last the longest.

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Re^2: Unexpected effect of -w with undef by DrWhy (Chaplain) on Dec 22, 2004 at 16:37 UTC
Aw.... Dang! /me smacks forehead. --DrWhy "If God had meant for us to think for ourselves he would have given us brains. Oh, wait..."	[reply]
Re^3: Unexpected effect of -w with undef by Aristotle (Chancellor) on Dec 22, 2004 at 16:41 UTC
Hehehehe. I looked at it in befuddlement for a moment as well after I pasted the code in a terminal and it didn't print a thing. Then I went “Oh! Heh, he'll be really embarrassed when he reads the answer.” Don't sweat it though, we all have our moments. `:-)` Makeshifts last the longest.	[reply]
Re^4: Unexpected effect of -w with undef by gellyfish (Monsignor) on Dec 22, 2004 at 16:43 UTC
What confused me is that `undef eq undef` is true, I guess indoctrinated by SQL hanDling of NULL I expect it to be undefined or false ... I guess this is not something that will get changed however. /J\	[reply] [d/l]
•Re^5: Unexpected effect of -w with undef by merlyn (Sage) on Dec 22, 2004 at 16:45 UTC
Re^5: Unexpected effect of -w with undef by Aristotle (Chancellor) on Dec 22, 2004 at 16:45 UTC