Description:
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explode on an empty string creates an array with a single blank element, instead of an empty array (with no elements).

This means that explode/implode do not yield reversible results when an empty array is used (though, they do otherwise -- when the array is non-empty).

This is a duplicate of #699, but I'm resubmitting since #699 was closed with no explanation a long time ago.

Reproduce code:
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$a = array();

$b = explode(":", implode(":", $a));

print "a: ";
print_r($a);

print "<p>b: ";
print_r($b);

Expected result:
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a: Array ( ) 
b: Array ( ) 



Actual result:
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a: Array ( ) 
b: Array ( [0] => )