9.13 Calculate expression then check condition

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In comparison operations the left operand can now contain calculations

of an expression, including increment and decrement. For example:

IF (i=a+2 != 0 )...

IF ( i++ )...

IF ( a-- )...

IF ( i+=4 == 0 )...

In all these example, first the expression in the left part of the

comparison operation is calculated, and then the result is compared with

the right part of the expression to be compared.