Re: Question on bounded / unbounded strings

["Björn Lundin" <b.f.lundin@gmail.com>]

On 2016-09-28 23:09, Randy Brukardt wrote:
> "John Smith" <yoursurrogategod@gmail.com> wrote in message 
> news:e60176b6-4c61-474a-a191-b31821816004@googlegroups.com...
> On Saturday, September 24, 2016 at 3:52:54 AM UTC-4, Dmitry A. Kazakov 
> wrote:
> ...
>> However, if I ever need string functionality that I'm used to in Python or 
>> C++,
> 
> Ada doesn't have it (sadly).
> 
> I used to tell people to use Unbounded_Strings, but that was before I tried 
> to build an application that way. (I discussed that further in a different 
> message in this thread). You have to revert to String in many places (which 
> is aggrevating [Ada 2005 did eliminate a couple of them, but it doesn't help 
> much], one has to look up the names of the operations beyond the most basic, 
> and if you are sensible use-adverse person (:-)), the names you have to use 
> are nasty (Ada.Strings.Unbounded.To_Unbounded_String ("Foo") -- gack!!!)
> 

Recently I needed to process xml files, and do a bit of string
manipulation with the results. I agree that Unbounded_String is clumpsy
(name-wise) and that Ada.Strings.Fixed has useful operations.
I ended up wrapping what I need in a new object - String_Object -
with naming I know will trigger people here :-)


with Ada.Strings;           use Ada.Strings;
with Ada.Strings.Unbounded; use Ada.Strings.Unbounded;


package Repository_Types is
  type String_Object is tagged private;

  procedure Set(Self : in out String_Object; What : String);
  procedure Reset(Self : in out String_Object);
  function Fix_String( Self : String_Object) return String;
  function UBString( Self : String_Object) return Unbounded_String;
  function Lower_Case( Self : String_Object) return String;
  function Upper_Case( Self : String_Object) return String ;
  function Empty_String_Object return String_Object;
  procedure Append(Self : in out String_Object; What : String);
  function Camel_Case(Self : String_Object) return String ;
  procedure Delete_Last_Char(Self : in out String_Object);

  function "<"( Left, Right : String_Object) return Boolean;
  function "="( Left, Right : String_Object) return Boolean;
  function ">"( Left, Right : String_Object) return Boolean;

private
  type String_Object is tagged record
    Value ,
    Camel_Case_Cache,
    Lower_Case_Cache,
    Upper_Case_Cache: Unbounded_String := Null_Unbounded_String;
  end record;

end Repository_Types;


To me, it turned out to be quite useful
-- 
--
Björn