Data Type Specification and Conversion like in FORTRESS

A major disadvantage of every spreadsheet application is the lack of 
coding capabilities to explicitly state the type of the values.

This *major design flaw* of spreadsheets makes them very error prone 
when intermingling  various data formats.

I really miss something like the new FORTRESS (see 
http://fortress.sunsource.net/).

In my primary work, I am overseeing 100+ employees working extensively 
with worksheets. Unfortunately, there were often  situations where 2 
currencies  were used, providing a perfect milieu for conversion errors, 
e.g. 1,000,000 RON equals approx. 300,000 Euro, BUT adding 1,000,000 or 
300,000 makes a great difference (of 700,000 RON or Euro). The 
globalisation trend will only  foster  this development.

The killer feature that  will differentiate spreadsheets from the 
'70-'80s from modern concepts would allow the user to specify the type 
of the data, e.g.:
 A1: 30 m
 A2: 125 cm
 A3: 86 inch
 A4:   = SUM(A1:A3) => implicit conversions are done

2nd example:
A1: 1.2 M Euro
A2: 0.67 M $
A3: =SUM(A1:A2) => implicit conversion using a pre-specified conversion rule

As this feature will differentiate the flawed concepts of the past from 
the modern  views, I hope that it gets implemented in the ODF specification.

Kind regards,

Leonard Mada