How to represent a "cost" in XML?

["Costello, Roger L." <costello@mitre.org>]

Hi Folks,

 

I would like to represent in XML the cost of something.

 

Here’s one way to represent it:

 

<Cost currency="USD">8.95</Cost>

 

If you didn’t want to use attributes (or mixed content), how would you represent it?

 

Would you represent it like this:

 

<Cost>
    <Currency>USD</Currency>
    <Value>8.95</Value>
</Cost>

 

I do not like that representation because it introduces a fake <Value> element.

 

Perhaps you would represent it by turning things inside out:

 

<Value>
    <Currency>USD</Currency>
    <Cost>8.95</Cost>
</Value>

 

I’m not sure I even know what that means.

 

Sigh.

 

Any economists out there? Please do tell: what is “cost”?

 

Cost seems to have (at least) two components: a number and an indication of what system of money the number is based on. The “system of money” is the currency. What about the number; what is it? What label do you give to the number? When you talk about the number, what words do you use?

 

/Roger