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// A is not assigned, so IsNum will be 0. Using Num() would have brokencaused toa theVNAV debuggererror.
IsNum = SRP_Num(A)

// B is "", which might cannotbe safelydifferent bethan used0 toin calculatethis C.application
// Num() would have returned 1 and calculating C would have causedassumed a"" debuggeris error.0
B = ""
If SRP_Num(B) then
	C = B + 1
end

Compile Function AddDivide(Num1Dividend, Num2Divisor)

    // The usual way of defaulting parameters, which will break stillthis breakroutine if Num1Divisor is ""
    If Unassigned(Num1Dividend) then Num1Dividend = 0
    If Unassigned(Num2Divisor) then Num2Divisor = 01

    // To be even safer, we need to check for both "" and unassigned... but this will break too
    // because BASIC+ evaluates all expressions in an condition, even if the first expression
    // makes the condition true. Thus, these statements will break to the debugger if Num1 orDividend Num2
    // isor Divisor are unassigned.
    If Unassigned(Num1Dividend) OR Num1Dividend EQ "" then Num1Dividend = 0
    If Unassigned(Num2Divisor) OR Num2Divisor EQ "" then Num2Divisor = 01

	// This is even safer, but the arithmeticsafest will breakway to theensure debuggerthis ifroutine Num1 or Num2 contains
    // non-digits or is too big to be a numbernever breaks to the bugger.
    If Unassigned(Num1Dividend) then
        Num1Dividend = 0
    end else
        If Num1Dividend EQ "" OR Not(Num(Dividend)) then Num1Dividend = 0
    end
    If Unassigned(Num2Divisor) then
        Num2Divisor = 01
    end else
        If Num2Divisor EQ "" OR Not(Num(Dividend)) then Num2Divisor = 01
    end

    // SRP_Num makes coversit allso themuch basessimpler
    Num1Dividend = SRP_Num(Num1Dividend, 0)
    Num2Divisor = SRP_Num(Num2Divisor, 01)

Return Num1Dividend +/ Num2Divisor