Calling Module Functions

[Chris Iverson]

I can't figure out what I'm doing wrong, and I'm fairly sure it shouldn't crash RB. I've got this very rudimentary code to use as a module(not permanently):

Print "Login module running."

Function Login(username$, password$)
   Print "Logging in..."
   open "user" for input as #file
   line input #file, uname$
   line input #file, pass$
   close #file
   Login = 1
   If username$ <> uname$ or password$ <> pass$ then Login = 0
End Function

Function Change(username$, password$)
   Print "Changing password..."
   open "user" for output as #file
   print #file, username$
   print #file, password$
   close #file
End Function


I try to run it with this code:

run "login", #login

a = #login Change("Iam", "auser")
render #login



And it crashes with the error 'Unhandled Exception: Subscript out of Range' or 'unhandled exception' and something to do with #x.

EDIT: I found the error, it's in the Login sub, OPEN needs to have a full path, e.g. "C:\rbp\login_project\user". Still don't think this should crash RB.

[carlgundel]

thedarkfreak said:

I can't figure out what I'm doing wrong, and I'm fairly sure it shouldn't crash RB. I've got this very rudimentary code to use as a module(not permanently):

Print "Login module running."

Function Login(username$, password$)
   Print "Logging in..."
   open "user" for input as #file
   line input #file, uname$
   line input #file, pass$
   close #file
   Login = 1
   If username$ <> uname$ or password$ <> pass$ then Login = 0
End Function

Function Change(username$, password$)
   Print "Changing password..."
   open "user" for output as #file
   print #file, username$
   print #file, password$
   close #file
End Function


I try to run it with this code:

run "login", #login

a = #login Change("Iam", "auser")
render #login



And it crashes with the error 'Unhandled Exception: Subscript out of Range' or 'unhandled exception' and something to do with #x.

EDIT: I found the error, it's in the Login sub, OPEN needs to have a full path, e.g. "C:\rbp\login_project\user". Still don't think this should crash RB.

You're right. It shouldn't crash, but that's what beta testing is for. Thanks!

-Carl

[carlgundel]

thedarkfreak said:

EDIT: I found the error, it's in the Login sub, OPEN needs to have a full path, e.g. "C:\rbp\login_project\user". Still don't think this should crash RB.

The full path is not required and in fact if works fine in general. However perhaps it is related to the fact that you are running an embedded component. Right now I'm working on documentation for RB, but maybe later today I'll take a break and try to track that down.

-Carl

[Chris Iverson]

Yes, I did notice that it worked fine when I just put the open command in a file alone, and not as a module. It also appears that if a file doesn't exist when you OPEN it for INPUT while the command is in a module, RB crashes.

[carlgundel]

thedarkfreak said:

Yes, I did notice that it worked fine when I just put the open command in a file alone, and not as a module. It also appears that if a file doesn't exist when you OPEN it for INPUT while the command is in a module, RB crashes.

When you say it crashes, do you mean the server crashes and you have to start it back up again, or do you mean that your program stops with an error indication in the browser?

Opening a non-existent file should cause a runtime exception, not a hard crash of the server.

-Carl

[Chris Iverson]

It's a hard crash; I think it says 'unhandled exception: subscript out of range' or something similar. Not the webpage, it's a notice that RB gives just before it goes PKEEWWWW.


Edit: It's 'Unhandled exception: Subscript out of bounds', so yeah, same thing. I think >_>

[Chris Iverson]

I've noticed that if you allow the program execution timeout to expire, the error goes away without RB crashing. I don't know if this has any repercussions or anything.

[turbov21]

Why is "Change" a function when it doesn't return a value?

[Chris Iverson]

For two reasons: 1. Because I don't think you can call subs in RB modules yet. At least, you couldn't in Beta 3. I forgot to check with beta 4.

And 2: Personal preference. For some reason, I have always avoided making my stuff subroutines. Although I still do in a lot of programs, I always gravitate toward functions. Don't ask me why.

EDIT: Confirmed, you can't called subs in a module. Only functions.

[Jerry Muelver]

Chris, you could have your no-returns functions return at least a success indicator -- 0 or 1. The you could say,

if Login(uname$,pword$) then...
else...

for a more logically flowing program narration.

[Chris Iverson]

Login does do that, I forgot