I'm curious by what criteria you judge that it "should have been." Do you mean that it should be there as a matter of good defensive programming style?

Nothing to do with style, but with correctness. Stuff like: 

    while (($line = <>) && $line =~ /\S/) { ... }
    while (($line1 = <>) && ($line2 = <>)) { ... }

[download]
Also, the standard way of translating a while to a for(;;) loop won't work: 
    for (;$line = <>;) { ... }

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And even: 
    next unless $line = <>;

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They are all cases where a defined test should be used, because otherwise you may get unwanted effects.

Abigail

In reply to Re: To Kill a Meme: while(defined($line = <>)) by Abigail-II
in thread To Kill a Meme: while(defined($line = <>)) by sauoq

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