Re: Get_Line

["Warren W. Gay VE3WWG" <ve3wwg@cogeco.ca>]

Robert A Duff wrote:
> "Chad R. Meiners" <crmeiners@hotmail.com> writes:
> 
> 
>>"Robert A Duff" <bobduff@shell01.TheWorld.com> wrote in message
>>news:wcc3cqn35wu.fsf@shell01.TheWorld.com...
>>
>>>But isn't the *real* problem that the design of Text_IO is broken?  For
>>>example, why is there no Get_Line function:
>>>
>>>    function Get_Line(...) return String;
>>>
>>>that returns the entire contents of the next line, no matter how long it
>>>is, and without fussing about with fixed-length (i.e. wrong length!)
>>>buffers?
>>
>>I wouldn't say broken.
> 
> 
> Why not, given that beginners have trouble with all that buffer
> management?  In fact, so do experts!  How does one choose the correct
> buffer size?
> 
> Whether or not you like my Get_Line idea, surely you must admit that
> beginners and experts are troubled by the current Text_IO interface.
> 
> 
>>...  Do you really want Ada.Text_IO to contain functions
>>with side-effects?

I would say no -- at least as much as is practical.

Consider a different interface:

with Ada.Strings.Unbounded;

...

    declare
       use Ada.Strings.Unbounded;
       Line : Unbounded_String;
    begin
       ...
       Get_Line(F,Line);  -- Non-standard Get_Line() here

Here Line can be returned as short or as long as required.  If you
later want a "native string", then add:

       declare
          S : String := To_String(Line);
       begin
          ...

-- 
Warren W. Gay VE3WWG
http://home.cogeco.ca/~ve3wwg