Using --debug-array with arrays passed to functions

[RandomiserUsr]

Hi everyone,

I would like to use the --debug-array option to check I have not used out-of-range array indices in my program. However, it appears that I need to give the compiler more information, to use the option in a program that passes arrays as function arguments.

For example, the following simple program appears to compile/ run correctly:

Code:

function pickString$( choice as ubyte,  listOfStrings() as string ) as string     return listOfStrings(choice) end function dim myString$(3) as string myString$(0) = "Zero" myString$(1) = "One" myString$(2) = "Two" myString$(3) = "Three" dim n as ubyte for n=0 to 3     print pickString$(n, myString$) next n stop

--but the compiler generates an error if I try to compile with the --debug-array option:

Code:

zxbc -t -a -B --debug-array array_bounds_ex.bas Traceback (most recent call last):   File "c:\opt\zxbasic-1.14.0\zxbasic\zxbc.py", line 10, in <module>     sys.exit(libzxbc.main())  # Exit   File "c:\opt\zxbasic-1.14.0\zxbasic\src\libzxbc\zxbc.py", line 246, in main     func_visitor.start()   File "c:\opt\zxbasic-1.14.0\zxbasic\src\arch\zx48k\translator.py", line 1401, in start     self.visit(f)   File "c:\opt\zxbasic-1.14.0\zxbasic\src\ast\ast.py", line 35, in visit     stack.append(last.send(last_result))   File "c:\opt\zxbasic-1.14.0\zxbasic\src\arch\zx48k\translator.py", line 196, in visit_ARGLIST     upper = node.parent.entry.bounds[i].upper   File "c:\opt\zxbasic-1.14.0\zxbasic\src\symbols\boundlist.py", line 29, in __getitem__     return self.children[key]   File "c:\opt\zxbasic-1.14.0\zxbasic\src\ast\tree.py", line 40, in __getitem__     return self._children[key] IndexError: list index out of range

I imaging the problem is that the compiler can't work out the array bounds within the function, unless I tell it. Anyone know if I can modify the source, so array-bound checking will still work?

Thanks in advance,

Hi, 

I have modified your code and it prints out what you expect 

Code:

dim myString$(3) as STRING dim n as ubyte myString$(0) = "Zero" myString$(1) = "One" myString$(2) = "Two" myString$(3) = "Three" function pickString$( choice as ubyte,  listOfStrings() as string ) as string     return myString$(choice) end function for n=0 to 3     print pickString$(n, myString$) next n

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Actually you don't need to pass in the listOfStrings() as string just this is needed:-

"function pickString$( choice as ubyte ) as string"