how to handle unexpected errors in large code?

Author

Message

dandrews

3

Years of Service

User Offline

Joined: 26th Jun 2020

Location:

Posted: 4th Jul 2023 15:29

Link

just seeing if anyone has suggestions for how to find and handle errors in code in a way that i can see whats happening instead of the app closing or the basic error message coming up. the basic error messages are a big help for sure, as of right now ive been putting do loops anywhere im having issues and printing whats happenig. So besides a "if error print this" after every line of code what are others doing? thanks!

Back to top

Profile PM

smerf

19

Years of Service

User Offline

Joined: 24th Feb 2005

Location: nm usa

Posted: 4th Jul 2023 17:50

Link

100% of your code should be inside functions essentially unless you use jumps from loop to loop. One method that is usefull i just putting a print of flag in the top of each function that updates as the prog runs. This will let you know the function that failed. From there you can isolate the code to a small area. Ive used the debugger maybe 10 times in 15 years the general error messages are pretty useful. so in each function gosub goto ect u can just have an update. i imagine u could get cool and cleaver with it and make it a function on its own like

+ Code Snippet

type Error
	Msg as string
	stepp as integer
	state as integer
endtype

function Debug(stepp as integer,msg as string)
	error.msg=msg
	error.stepp=stepp
endfunction "Error Code:("+str(error.stepp)+") "+error.msg

function DebugPause(stepno)
	local ret as integer
	if error.stepp=stepno then ret=1
endfunction ret

function PrintDebug()
	Print(error.msg)
endfunction

function dostuff()
	debug(1,"mydostuff function)
	Print("if there is an error")
	Print("in this function anywhere")
	print("it will crash")
	print("but we dont want to comment")
	print("every single line of")
	debug(2,"im just a fancy ass print statement")
	print("code cause that would be")
	print("stupid")
	Debug(3,"this code crashed cause I need coffee")
	print("so we can add in steps for the debugger")
	print("so we can isolate the code")
	print("to sections")
endfunction


do

	doStuff()
	`all the code in the world
	printDebug()
	sync()
loop

Back to top

Profile PM Email

blink0k

Moderator

11

Years of Service

User Offline

Joined: 22nd Feb 2013

Location: the land of oz

Posted: 4th Jul 2023 17:55

Link

Have you tried using debug?

Back to top

Profile PM

PartTimeCoder

AGK Tool Maker

9

Years of Service

User Offline

Joined: 9th Mar 2015

Location: London UK

Posted: 4th Jul 2023 18:51 Edited at: 4th Jul 2023 19:01

Link

Yup, as blink0k says use debug

to clarify, Use the Log("Your string") function to print out the state of your variables and run the game in debug mode, if your variables are numbers be sure to wrap them in the Str() function ... Log is also a math function when used with numbers! .... weird they did that Id have called it Debug but NM!

Edit: combine with smerf's approach and you got a pretty good reporting system, I would only go to such lengths with real problem areas tho!

you can also use the variable watcher but its easier just to "Log" .... unless its really problematic code then you want to use the debugger to its fullest and stick vars on the watch list and step into/out of code ... I never had to go that far to be honest, not with AppGameKit, C++ on the other hand the debugger is your best friend!! lol

Open Source plugins
Cl - DnD Plugin
Buy Me A Coffee

Attachments

Login to view attachments

Back to top

Profile PM

dandrews

3

Years of Service

User Offline

Joined: 26th Jun 2020

Location:

Posted: 4th Jul 2023 19:26

Link

thanks all. im asking because some functions i use multiple place of course so when i get an error it doesnt really tell me what function it came from to produce the error

Back to top

Profile PM

PartTimeCoder

AGK Tool Maker

9

Years of Service

User Offline

Joined: 9th Mar 2015

Location: London UK

Posted: 4th Jul 2023 19:54

Link

Yea a Lua type stack trace system would be nice you can get the calling function further up the stack, but alas!

you could implement your own pseudo stacktrace if you have a problematic function called from multiple places

something like

+ Code Snippet

Function MyFunction(arg1, arg2, arg3, sCalledFrom As string)


  Log("MyFunction("+arg1+", "+arg2+", "+arg3+")")
  Log(sCalledFrom+"()")
EndFunction

// somewhere Else in the code
  
Function SomeOtherFunction() 

  argA = 123
  argB = 456
  argC = 789

  MyFunction(argA, argB, argC, "SomeOtherFunction()")

EndFunction

But it would have to be giving me serious headaches for me to go to those lengths

Open Source plugins
Cl - DnD Plugin
Buy Me A Coffee

Back to top

Profile PM

blink0k

Moderator

11

Years of Service

User Offline

Joined: 22nd Feb 2013

Location: the land of oz

Posted: 4th Jul 2023 23:27

Link

Debug shows you the stack

Back to top

Profile PM

PartTimeCoder

AGK Tool Maker

9

Years of Service

User Offline

Joined: 9th Mar 2015

Location: London UK

Posted: 5th Jul 2023 01:37

Link

Ha!, Shows how little I've used it!

Is there a video showing the full usage of the debugger, if not, there should be

Open Source plugins
Cl - DnD Plugin
Buy Me A Coffee

Back to top

Profile PM

dandrews

3

Years of Service

User Offline

Joined: 26th Jun 2020

Location:

Posted: 5th Jul 2023 02:16

Link

yeah it would be great to see it in use

Back to top

Profile PM

blink0k

Moderator

11

Years of Service

User Offline

Joined: 22nd Feb 2013

Location: the land of oz

Posted: 5th Jul 2023 02:59 Edited at: 5th Jul 2023 03:01

Link

F8 to start debugger
1. Top left you can see the Stack. I'm pretty sure it's the same with classic
2. The red dots are breakpoints, you can set them by clicking on that column
3. Hover over a variable and it will show you it's contents
4. You can add "watch" variables at the left where you can modify their contents

There's a lot of other functionality I am not familiar with. I think there are a few videos on YouTube by TGC demonstrating the finer details

Trust me, spend a few minutes with it and it will radically change and speed up the way you develop stuff.

Back to top

Profile PM

Sorry your browser is not supported!

AppGameKit Studio Chat / how to handle unexpected errors in large code?

Attachments