Re: Data table text I/O package?

[Marius Amado Alves <amado.alves@netcabo.pt>]

On 16 Jun 2005, at 10:55, Jacob Sparre Andersen wrote:

> Randy Brukardt wrote:
>
>> I may be dense, but isn't this the purpose of XML? If so, why
>> reinvent the wheel?
>
>  d) I'm _not_ going to switch away from tabulator separated tables for
>     purposes, where tabulator separated tables are a sensible
>     representation of the data in textual form.

Indeed. XML is for semi-structured data and/or text data with Unicode 
etc. For tables of atomic data tab separated is better. More readable, 
efficient, sensible, not requiring a monster XML library.

> It is the matter of
> automagically generating code for reading and writing that file
> format.

Yes. This is interesting, useful, and easy. From the header you get the 
field names, from the first data line with deduce the data types. With 
these elements you can generate the record type and procedures to read 
the file. A trick I often use to deduce data types is based on 'Value:

function Get_Type (Value : String) return Data_Type is
    F : Float;
    I : Integer;
begin
    F := Float'Value (Value);
    return Type_Float;
exception
    when Constraint_Error =>
       begin
          I := Integer'Value (Value);
          return Type_Integer;
       exception
          when Constraint_Error =>
             return Type_String;
       end;
end;