Re: [office-formula] User-Defined Functions

[Eike Rathke <erack@sun.com>]

Hi Robert,

On Thursday, 2010-06-03 11:42:12 -0400, Robert Weir wrote:

> > They have been briefly discussed. The outcome was that implementations
> > should write them prefixed with "USER.", this seems not to have made it
> > into section 5.7
> 
> 
> Should there any difference between an implementation-specific extension 
> function and a user-specific extension function?  I think there might also 
> be 3rd party libraries of extension functions.

Implementation-specific extension functions should start with domain
names as lined out in section 5.7, e.g. ORG.OPENOFFICE.* or COM.MICROSOFT.*

I think the "USER." prefix should be applied to all extension functions,
user-defined or third party, that do not use the domain name approach.

> Main concern now is name collisions.  Simply saying USER.CurrencyConvert() 
> may prevent the name from colliding with future intrinsic functions in 
> OpenFormula that might use the name "CurrencyConvert", but it doesn't 
> prevent collisions between two users with the same function name.

I don't see how we could prevent that. Introducing some sort of per
document prefix or UUID would still not help for or disable library
functions that have the same name on different systems / user
installations and are doing actually the same. We can only recommend to
library developers to use the domain name approach.

  Eike

-- 
Automatic string conversions considered dangerous. They are the GOTO statements
of spreadsheets.  --Robert Weir on the OpenDocument formula subcommittee's list.

PGP signature