I didn't attempt to cater for your test ii because it was not part of the original specs. tadman said.

As a note, the 'new' value is always present, even if it is undef.

If I remove all whitespace and newlines, redundant ;'s etc from my solution above it comes out to 87 

sub f{local($^W,$a)=(0,pop);grep{!exists$a->{$_}{O}or$a->{$_}{O}ne$a->
+{$_}{C}}keys%$a} #87

[download]

Then I noticed that I could save a couple more whilst still retaining a 'safe' function (ie. doesn't stomp on any globals) by switch to mying $a for 85 

sub g{local$^W=0;my$a=pop;grep{!exists$a->{$_}{O}or$a->{$_}{O}ne$a->{$
+_}{C}}keys%$a} #85

[download]

but I go the whole hog and abandon safety completely, this can be reduced further (and neatly, below the traditional 80 char line) to 78.... 

sub h{$^W=0;$a=pop;grep{!exists$a->{$_}{O}or$a->{$_}{O}ne$a->{$_}{C}}k
+eys%$a} #78

[download]
Cor! Like yer ring! ... HALO dammit! ... 'Ave it yer way! Hal-lo, Mister la-de-da. ... Like yer ring!

In reply to Re: Re: (Golf) Warningless Comparison by BrowserUk
in thread (Golf) Warningless Comparison by tadman

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