Re: array of string

[brbarkstrom@gmail.com]

On Friday, October 3, 2014 7:29:15 PM UTC-4, Stribor40 wrote:
> is there way to declare array of strings to contain something like this..
> 
> 
> 
> a(1)="london"
> 
> a(2)""toronto"
> 
> 
> 
> how would i create this?

You could also create an array of Bounded_Strings.  When you set up such
an array, you can specify the maximum size.  Then when you assign a particular
array element, you use the Bounded_Strings package functions to assign a
string to the array.  In other words, you can write

Std_Vstring_Length : constant := 256;
package Vstring is new Ada.Strings.Bounded.Generic_Bounded_Length(Std_Vstring_Length);

Then you should be able to define

Max_Array_Size : constant := 10; -- or whatever the number of strings you want
Bounded_String_Array : array (1 .. Max_Array_Size) of Vstring.Bounded_String;

later, you can do things like

Bounded_String_Array(1) := Vstring.To_Bounded_String("london");
Bounded_String_Array(2) := Vstring.To_Bounded_String("toronto");

If you want to print the strings, you can do things like

Text_IO.Put(Vstring.To_String(Bounded_String_Array(1)));

which should output just london

while 

Text_IO.Put_Line(Vstring.To_String(Bounded_String_Array(2)));

would ouput toronto on a single line.

There are a number of useful functions, including Slice and Element
in the Bounded_Strings package.  You can even use Direct_IO to 
save the elements of the array Bounded_String_Array so you can
retrieve them by doing 

package Bounded_String_DIO is new Direct_IO(Bounded_String_Array); use Bounded_String_DIO;

Then you can do things like

Bounded_String_DIO.Write(File => Bounded_String_DIO_File,
                         Item => Bounded_String_Array(4),
                         To   => Bounded_String.Positive_Count(4));

and read it with

Bounded_String_DIO.Read(File => Bounded_String_DIO_File,
                        Item => Selected_Bounded_String,
                        From => Bounded_String.Positive_Count(4));

which will read the Bounded_String_Array element 4 into 

Selected_Bounded_String : Vstring.Bounded_String;

Hope this helps.

Bruce B.