Is this my failure or of the compiler's debugger

[ldries46]

I try to create a program that read Unbounded strings from a file in the loop:
      Open(C_File, In_File, To_String(Inp_File));
      while not End_of_File(C_File) loop
         str_line_n := To_Unbounded_String(Get_Line(C_File));
         Buffer_GL.Set_Buffer(str_line_n); -- breakpoint on this line
         glade_lines := glade_lines + 1;
      end loop;
      Close(C_File);
where str_line_n is of the type Unbounded_String.
I used a test file with the below presented three text lines:
Line 1 abcdef9876543210
Line 2 " abcdef"9876543210
Line 3 "abc"de"f"9876543210

In the debugger the results were:
"Line 1 abcdef 9876543210"
"Line 2 "" abcdef"" 98765432"
"Line 3 ""abc""de ""f""987654"

I used:
GNAT Studio 23.0w (20220512) hosted on x86_64-w64-mingw32
GNAT Community 2021 (20210519-103) targeting x86_64-w64-mingw32
SPARK Community 2021 (20210519)

My questions are:

• Are the double quotes problems for the debugger.
• Are the double quotes problems for reader subroutine.
  
• How can I see the real values in the debugger.

What is the most simple way to solve this problem.

[AdaMagica]

The double quote within a string just represent one character: "
Thus this string's length is 1 """".

[Niklas Holsti]

On 2023-01-10 15:16, ldries46 wrote:
> I try to create a program that read Unbounded strings from a file in the
> loop:
>       Open(C_File, In_File, To_String(Inp_File));
>       while not End_of_File(C_File) loop
>          str_line_n := To_Unbounded_String(Get_Line(C_File));
>          Buffer_GL.Set_Buffer(str_line_n); -- breakpoint on this line
>          glade_lines := glade_lines + 1;
>       end loop;
>       Close(C_File);
> where str_line_n is of the type Unbounded_String.
> I used a test file with the below presented three text lines:
> Line 1 abcdef9876543210
> Line 2 " abcdef"9876543210
> Line 3 "abc"de"f"9876543210
>
> In the debugger the results were:
> "Line 1 abcdef 9876543210"
> "Line 2 "" abcdef"" 98765432"
> "Line 3 ""abc""de ""f""987654"

It seems that the debugger displays the strings in the form of Ada
string literals, which are enclosed in quotes (") and within which each
quote character has to be duplicated (to show that it is not the
terminating quote). So the duplication of the quotes is nothing to worry
about. If you were to print out the strings (with Ada.Text_IO) they
should appear just as in the input, with only the original quote characters.

However, your example also shows some extra blank spaces in the debugger
output, for example:

Input : Line 1 abcdef9876543210
Debugger: "Line 1 abcdef 9876543210"

There seems to be a new blank space between 'f' and '9'. Are you sure
that you presented the input and output correctly?

[ldries46]

Op 10-1-2023 om 19:12 schreef Niklas Holsti:

Not only that but also some of the  last characters disappear in line 2
the 10 and in line 3 3210

[ldries46]

Op 10-1-2023 om 23:17 schreef ldries46:

In the mean time by inserting a write command to a Gtk window I found
that the problem is really a problem of the debugger. The values in the
Gtk window are correct. this means that in a next version of the
debugger that must be corrected

[Niklas Holsti]

My guess is that these differences are bugs in the debugger's display of
strings with embedded quote characters. For Line 1, which has no
embedded quotes, the full string is displayed (though with an inserted
blank). For Line 2, with two embedded quotes, two of the last characters
are not displayed. For Line 3, with four embedded quotes, four of the
last characters are not displayed. It seems that the debugger does not
realize that doubling the quote characters makes the displayed string
longer...

Try to print the strings with Ada.Text_IO instead, that should give the
right result. In other words, your code reading the strings works, but
the debugger is probably buggy. (One reason why I avoid debuggers
whenever I can.)

[ldries46]

Op 11-1-2023 om 14:43 schreef Niklas Holsti:

That is also my guess but I like to use the debugger because You stop
running the program anywhere you want and check all parameters you think
are nice to know. Now you have to add a lot of code and still see that
you need tyo know another parameter and run the program over and over
again each time with other code added.