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While Statement

 
Ranch Hand
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i want to obtain a value and assign it to b in a while statement and i also want to test to see if B is null in the same statement, Please how do i do this


I tried but it resulted in errors

 
Wanderer
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Just add some parentheses to clarify the order:
 
Sheriff
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!= has precedence over =, so if you write it without parentheses the compiler will see this:

Now seeing as b is not a boolean, this will fail.

If you add parentheses as Jim has done, the compiler will have no problems anymore; it will first use the assignment to b, and only then compare the value of b to null.
 
Abiodun Adisa
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thanks
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