• From: Michael Kay <mike@s...>
• To: Roger L Costello <costello@m...>
• Date: Sun, 10 Jul 2022 15:19:03 +0100

> 
> Little languages provide a powerful way to quickly implement robust tools.
> 
> Reading the book made me keenly aware of one thing: The XML data format is complex! Compare the densely written 36-page XML specification (plus the 16-page namespace specification) to this three-sentence specification of a data format:
> 
> The data format consists of lines. Each line contains fields. Fields are separated by a delimiter (space, tab, comma, etc.).
> 

In my opinion that's a lousy specitication, and lousy specifications like that account for an immense about of trouble in our industry.

What's missing?

* It doesn't say what a line is. How are lines separated or terminated?

* What on earth does "etc." mean?

* It says how fields are separated, but it doesn't say what can appear within them. What happens when the value of a field contains a separator?

* It says nothing about character encoding.

* Does every line have to contain the same number of fields?

* Can fields be empty?

The only reason the specification is short is that it's woefully incomplete.

Michael Kay
Saxonica

• References:
  • The impact of data format selection on application development
    • From: Roger L Costello <costello@m...>