Tuples with named attributes

[Nathan Allan]

Has any consideration been given to the possibility of tuples with named 
identified attributes, rather than ordinally identified attributes?  Named 
attributes are much more useful to humans, as is evidenced by the fact that 
we use named rather than numbered identifiers in programming languages.  In 
my view, tuples, as implemented in D, would be much more useful with named 
attributes.

To illustrate my point, consider what a relation (table) type might look 
like in D.  In the relational model of data, a relation is composed of n 
tuples having the same named attributes.  This allows us to define the 
relation type as a set of the name : type attribute definitions.  Imagine 
working with a database where the attributes of each relation variable were 
numbered rather than named!

Number indexed tuples are much more difficult to grok than named ones.  A 
name indexed tuple can be easily understood to any developers as an 
"anonymous struct".  Having helped design and use a language (D4) with 
native support for tuples in their named form, I can attest to their 
usefulness.   One example of their power is as an orthogonal means to return 
multiple results from a function.  Rather than a bizarre mixture of return 
values and output parameters, a set of named values can be easily returned.

In D4 you can do stuff like this:

var name := GetName();
...name.First...
...name.Last...

there are also join, rename, and extend/project operators included with the 
language:

GetName() { First FirstName /* rename */, First.ToUpper() UpperFirst /* 
extend */ } join GetAddress()
/* result is a tuple (called a row in D4) with FirstName, UpperFirst, and 
address attributes) */

...highly recommended!

Regards,

--
Nathan Allan