[regext] Warren Kumari's No Objection on draft-ietf-regext-epp-fees-18: (with COMMENT)

[Warren Kumari via Datatracker <[e-mail]>]

Warren Kumari has entered the following ballot position for
draft-ietf-regext-epp-fees-18: No Objection

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COMMENT:
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Firstly, thank you for working with Carlos to address the OpsDir comments -- he
raised some good points (and is nicer than me), so I'm going to be a bit more
of a stickeler than he was.

"A <fee:fee> element MUST have a non-negative value." -- Yes, zero is a
non-negative value (Hi Barry!), but not listing it explicitly seems like it's
just asking for someone to do something like: ## Estimate how many transactions
like this we can do: total_balance / fee or something similar. Simply
mentioning the word should help lazy coders take this corner case into account.

How would:
 A <fee:fee> element MUST must have a zero or greater value
work for you?

Also, I must admit I found this bit surprising:
"A <fee:credit> element MUST have a negative value."

If I go to Payless and return a pair of shoes, they give me a **credit** of
$20, not of -$20. I really think that the credit element should either be
treated in the same way, or you could do away with the credit elemans and just
have negative "fees" (if I open my credit-card bill and see a charge of -$20 I
know what it means), or if you don't want to do that,  provide some clear
warning text around this section. If I were implementing this, and not paying
sufficient attention I'd calculate "new_balance = old_balance - fees + credits"
-- a simple phrase or two should help prevent stupid errors.