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- Subject: Re: false [was: The "Is nil present in a table" problem}
- From: "John Belmonte" <jvb@...>
- Date: Thu, 29 Nov 2001 01:25:57 +0900
Paul Chakravarti wrote:
> I would prefer that this explicitly evaluated to a
> distinct 'true' type - if there is no explicit 'true' value
> it is impossible to correctly serialise the value for
> an API which expects a destinct boolean value (in
> this case specifically XMLRPC but generally true) by
> checking the type.
Scheme is a pretty serious as far as languages go and it manages to get by
with just a false type.
Maybe expecting tables (or the language) to support full marshaling
out-of-the-box is too much. There are still cases where you want some type
associated with each field but want to allow for nil values. For example
field "email_address" is a string but it happens to be nil right now meaning
it's invalid or undefined. When you need that you're back to Rici Lake's
table of tables technique.