Re: Sequental IO and pointers

[ejijott@gmail.com]

As an ad hoc solution my Save and Load procedures now work, as follows:

>
    procedure Save(S: Storage; File: String) is
        type ord is record
                item:  string(1..50);
                len:   integer :=-1;
                count: integer := 0;
        end record;

        package OrdlistaIO is new Sequential_IO(ord);
        use OrdlistaIO;
        fh_ordlista:OrdlistaIO.File_type;
        tnode:Storage;
        ord_att_spara:ord;
    begin
        tnode:=S;
        Create(fh_ordlista, Name=>file);
        while tnode /= null loop
            ord_att_spara.item(1 .. tnode.len):=tnode.item(1 ..
tnode.len);
            ord_att_spara.len:=tnode.len;
            ord_att_spara.count:=tnode.count;
            Write(fh_ordlista, ord_att_spara);
            tnode:=tnode.next;
        end loop;

        close(fh_ordlista);
    end Save;

    procedure Load(S: in out Storage; File: String) is
        type ord is record
                item:  string(1..50);
                len:   integer :=-1;
                count: integer := 0;
        end record;

        package OrdlistaIO is new Sequential_IO(ord);
        use OrdlistaIO;
        fh_ordlista:OrdlistaIO.File_type;
        inläst_post:ord;
    begin
        Open(fh_ordlista, Name=>file, Mode=>In_file);
        while not END_OF_FILE(fh_ordlista) loop
            Read(fh_ordlista, inläst_post);
            for i in 1 .. inläst_post.count loop
                Append(S, inläst_post.item(1 .. inläst_post.len));
            end loop;
        end loop;
        Close(fh_ordlista);
    end Load;
<

The Append procedure adds my input record to the end of my linked list
and all is well... but still, something tells me there should be some
sort of prettier/faster implementation to use here... In the assignment
we are supposed to make functions to read both normal textfiles
(strings after eachother) and binary files... I really dont see how a
simple thing like this could benefit from using binary files.