Search code examples
cexpressionevaluationunary-operator

What is the purpose of the unary plus (+) operator in C?

In C, it's legal to write something like:

int foo = +4;

However, as far as I can tell, the unary plus (+) in +4 is a no-op. Is it?

Solution

  • As per the C90 standard in 6.3.3.3:

    The result of the unary + operator is the value of its operand. The integral promotion is performed on the operand. and the result has the promoted type.

    and

    The operand of the unary + or - operator shall have arithmetic type..