sub sum { eval 'pop(@_)+' x ($#_ + 1) . '0'; }

@list = (-4, 15, -5, 2.5);
print sum @list;            # 8.5, as expected
print sum -4, 15, -5, 2.5;  # Works the same
print sum;                  # 0 (not undef)

[download]
EDIT: replaced $#list with $#_ , so that it works with lists of any length. Silly me.

In reply to Re^3: (almost) foldl by Grimy
in thread (almost) foldl by dk

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