A coworker ran into a problem parsing some data, here's an example: 
$_="|" x 5;
@foo = split /\|/,$_;
print scalar @foo; # prints 0

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he expected @foo to have 6 elements. According to the perl documentation:
Splits a string into a list of strings and returns that list. By default, empty leading fields are preserved, and empty trailing ones are deleted.
So if there are no fields to be parsed by the split, then it treats them all as empty trailing fields. My coworker said, "I think of them as empty leading fields!" The solution is to split as such: 
@foo = split /\|/,$_,-1

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to set an arbitrarily large limit and force split to treat them as empty leading fields, but that doesn't seem like the right (read: perl) way for things to happen. I'd expect perl to gracefully treat complete pseudo-emptiness as something, rather than nothing.

In reply to splitting nothing? by bageler

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