Omnimaga
Calculator Community => TI Calculators => Axe => Topic started by: Michael_Lee on November 24, 2010, 12:17:16 am
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In Axe, what precisely does DiagnosticOff and DiagnosticOn do? The documentation states that it turns off the run indicator, plus prevents 'Done' from displaying, but the run indicator is never on normally (I think). The User's Guide states that it leaves your code cleaner: in what way?
In Axe, are there any penalties for using Goto? If I did this:
For(X,0,9)
Lbl EX1
End
Goto EX1
What would that do?
What about this?
Lbl EX2
Repeat...
While...
If...
Goto EX2
End
End
End
And this?
Goto EX3
Repeat...
While...
If...
Lbl EX3
End
End
End
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The diadlgnostic off is really firllor changing in the middle of a program. And the axe gotos have no memory leaks like basic, to just sucked. :P
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In Axe, what precisely does DiagnosticOff and DiagnosticOn do? The documentation states that it turns off the run indicator, plus prevents 'Done' from displaying, but the run indicator is never on normally (I think). The User's Guide states that it leaves your code cleaner: in what way?
In Axe, are there any penalties for using Goto?
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The run indicator is an OS interrupt. It's always on unless you shut it off.
As for Goto in Axe, it works slightly differently in Basic. In BASIC, the OS maintains a list of all of the conditionals and loops that it's working with. When you skip out of a conditional without going through the proper number of End commands, the calculator doesn't know to return the memory blocks holding those commands. In theory the OS should return all of the memory blocks back to the calculator after the program is finished executing. However, due to a programming error in the OS, it "loses track" of a few of them and those memory blocks are never returned. Run the program enough times and you'll find yourself very short on RAM. That's when Garbage collect should automatically kick in and return those blocks to the calculator.
In Axe, Gotos are completely different. What a Goto does is change what location in RAM the calculator looks for the next instruction at. The calculator doesn't record the end statements, so there's no potential for memory leaks. You can abuse the Goto command as much as you want without fear. Just remember to always return from subprograms because not doing so WILL cause memory leaks.
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The reason why the run indic might not be showing up is because you probably update that region of the screen so often that it makes it near impossible to see. I had this happen in Reuben Quest series.
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In Axe, what precisely does DiagnosticOff and DiagnosticOn do? The documentation states that it turns off the run indicator, plus prevents 'Done' from displaying, but the run indicator is never on normally (I think). The User's Guide states that it leaves your code cleaner: in what way?
The run indicator crawls the ants every time you use an OS bcall in your program. There are a lot of Axe commands that rely on these bcalls like for instance getkey (without parenthesis) or archiving/unarchiving. Commands like these will indeed show the run indicator.
For(X,0,9)
Lbl EX1
End
Goto EX1
It would go to the next cycle of the for loop. Whatever value X is at the moment will be the value it compares against to see if it should go to the next iteration.
Lbl EX2
Repeat...
While...
If...
Goto EX2
End
End
End
It will restart the loop from the beginning, similar to what "continue" does in C.
Goto EX3
Repeat...
While...
If...
Lbl EX3
End
End
End
It will jump to the middle of the loop. But probably the conditional statements for the Repeat, While, and If will be using variables you need to make sure are all initialized correctly if you want to just jump in and expect things to work.
The only potential memory leak is if you try to jump out of a subroutine. So be very careful if you attempt some weird optimization with that.
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Wait, using getkey/archive/unarchive causes the run indicator to re-appear even if it was disabled?
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Not if you disable it. But its on by default. You just sometimes don't notice it in some asm programs because it depends on the commands you use.
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Ah ok, thanks for the info. I think in CODEX, the archive/unarchive functions turned the indicator ON again if you disabled it. X.x
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Muhahaha! Sweet.
No penalties, except in subroutines!
No more having to create elaborate 'While' or 'Repeat' loops to manage program flow!
Now the only thing I have to worry about is the occasional velociraptor (http://xkcd.com/292/).
*Michael wanders off whistling, planning.
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Muhahaha! Sweet.
No penalties, except in subroutines!
No more having to create elaborate 'While' or 'Repeat' loops to manage program flow!
Now the only thing I have to worry about is the occasional velociraptor (http://xkcd.com/292/).
*Michael wanders off whistling, planning.
Well, you can still jump around in subroutines, and even sub-sub-routines (however deep it is). Just remember to always return back for each one (instead of jumping back to the loop), and it should be fine.
And I love using Goto in Axe programs. Occasionally I use it as the main loop of the program (Lbl LP:...:.code here:...:Goto LP:Lbl LE:End).
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Now the only thing I have to worry about is the occasional velociraptor (http://xkcd.com/292/).
I dont get the cartoon... ???
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The author is stating that the usage of 'goto' is so bad, that using it will cause a velociraptor to appear and kill you.
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Now the only thing I have to worry about is the occasional velociraptor (http://xkcd.com/292/).
I dont get the cartoon... ???
I really like that one. Tis' very funny. :P
Basically, using Goto is a bad thing. The cartoon's saying that gotos are bad. That's about all. :P
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Now the only thing I have to worry about is the occasional velociraptor (http://xkcd.com/292/).
I dont get the cartoon... ???
I really like that one. Tis' very funny. :P
Basically, using Goto is a bad thing. The cartoon's saying that gotos are bad. That's about all. :P
And so Axe is a pretty bad influence on comp coders ;D
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Yah. Which is probably why I'm having a wobber of a time trying to understand classes in Python.
But on the plus side, I understand pointers (probably)
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Well in z80 assembly, I think most of the time you use stuff like Gotos to jump elsewhere in RAM. I recommend being careful when using Goto in high level languages, though, because when used in large scale the program can become messy pretty fast (and hard to read).