Re: Enumeration I/O

[mheaney@ni.net (Matthew Heaney)]

In article <34DF9BBF.9FEA859B@er.uqam.ca>, Melanie Shatilla
<hj791520@er.uqam.ca> wrote:


>I've declared an enumeration type with character literals, and a
>variable of this type, for example :
>    TYPE Symbols is ('%', '$', 'a');

Don't name a type with a plural, unless it refers to a composite object. 
An instance of the Symbol(s) type contains only a single value, so that's
how you should name the type:

type Symbol is ('%', '$', 'a');

>    Symb : Symbols := '$';
>
>    package Symbols_IO is new Text_IO.Enumeration_IO(Symbols);
>
>When I give the instruction :
>    Symbols_IO.Put(Symb);
>
>...I get the right symbol but with the quotes (and I don't want them).

That is the defined behavior: character literals print out using the quotes.

>Obviously, I've thought of writing something like :
>
>    If Symb = '$' then
>        Text_IO.Put ('$');
>    end if;
>
>..but there must be a more convenient way, I hope! Any suggestions
>anyone ?

You could implement a table:

   type Symbol_Character_Array is
      array (Symbol) of Character;

   function To_Character : constant Symbol_Character_Array :=
     ('%' => '%', 
      '$' => '$', 
      'a' => 'a');
begin
   Text_IO.Put (To_Charcter (Symb));

Another thing you can do is Put the Symbol object to a string, then just
print the middle character of the 3-byte string.

declare
   Symbol_As_String : String (1 .. 3);
   Symbol_As_Character : Character renames Symbol_As_String (2);
begin
  Put (To => Symbol_As_String, Item => Symb);
  Put (Symbol_As_Character);
end;