What is the purpose of the unary '+' operator in C?

As per  C90 standard The result of the unary + operator is the value of its operand. 

So in C it is legal to write something like:

int a= +2;

 But i want to know is there any important reason to use unary + operator in C? Or it is just for completeness purpose?please someone explain with example.

Pritam Prasun @pritam 5 Apr 2015 08:55 pm

It seems that unary + has more importance than just completeness. It actually performs integral promotion of operand. I found a discussion thread on stackoverflow. Following is the link: