I am still getting used to Perl. I am wondering about the eval function. At what point of processing the script does an eval function get parsed ? Is it not compile time ? Or is it run time ? I don't even know. Also, why does 
if(require "module/that/does/not/exist") {
   print "loaded module ok\n";
}else{   
   print "could not load module $@\n";
}

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not work ?

Does require not return anything ? Because if I do 
eval { 
    require "module/that/does/not/exist";
}

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nothing happens ? Do I have to check $@ after eval ? Do i have to check if $@ is defined after every eval call ?

Also, why does this small print statement not generate error ? 
print petrol "hello there !";

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And why does 
eval { 
    print petrol "hi";
}

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get executed ok also ???? Please advise. What are some every day uses of eval, which are actually usefull ?

In reply to Question about eval by tiny_tim

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