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renojim's avatar
renojim
Community Streaming Expert
10 years ago

Working with LongInteger

I'm just taking a look at roLongInteger. As far as I can tell, it suffers from the same shortcoming as roDouble. Namely, there's no way to go back and forth to/from strings. Am I missing something? I have some monotonically increasing values that I'm worried will eventually overflow 32-bits. Currently I store them in the registry using toStr() and then use toInt() to convert the string back to an integer. There's no toLongInt() that I've found.

When I ran across this issue with doubles, I used Eval. The same thing could be done for LongInts:
BrightScript Debugger> lintstr = "8589934592&"
BrightScript Debugger> Eval("x& = " + lintstr)
BrightScript Debugger> ?type(x&), x&
LongInteger      8589934592

Now I've been told that Eval has been deprecated and also leaks memory. So... am I missing something simple? Is there really a problem if I use Eval a half a dozen times or so at the beginning of my code and then never again until it exits?

-JT
Roku Developer Program

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  • renojim's avatar
    renojim
    Community Streaming Expert
    10 years ago
    I'm counting total pennies in one of my games. It's purely informational and may or may not ever need more than 32 bits. I just figured I'd use LongInteger since it's available. If it weren't and the counter just wrapped around, it would be no big deal.

    -JT
  • EnTerr's avatar
    EnTerr
    Roku Guru
    10 years ago
    If one gets a penny for every second they play, it will take 2^31 seconds or 68 years to reach the horizon and they'll have $21M at that point
    (do you offer cash out option? :twisted: )

    For counting money though, just use Double - per IEEE it's guaranteed to preserve at least 15 digits during conversion. Which means you can hold amounts up to the US federal budget ($3+ trillion) with precision down to a cent. The nice thing is that even if exceeding that, it will start "failing" in a nice way, i.e. losing the cents like IRS does. Not to mention there is 2 hidden digits precision (it works internally at 17 decimal digit precision equivalent).
  • renojim's avatar
    renojim
    Community Streaming Expert
    10 years ago
    But what if it's 1000000 pennies at a time? 😄
  • EnTerr's avatar
    EnTerr
    Roku Guru
    10 years ago
    "renojim" wrote:
    But what if it's 1000000 pennies at a time? 😄

    Then you can afford yourself ~2000 of these $10,000 wins.

    Or if you switch to Double - which i advocate - then can handle 1,000,000,000 events like the above, which if they happen 1/sec would take 30+ years to lose the penny precision (not to overflow!). And after that, umm... why do you exactly need to pinch every penny? 😛
  • renojim's avatar
    renojim
    Community Streaming Expert
    10 years ago
    Nope. I learned long ago that dealing with currency as integers is far safer than using floats of any kind.