[Rd] setGeneric

[Luke Tierney]

On Tue, 1 Apr 2003, John Chambers wrote:

> I think this is a consequence of the extra context added to make methods
> work right with R lexical scoping, namespaces, etc.  Or a subtlety in
> R's definition of missing()?
> 
> The problem is that somehow the default expression for argument `ncol'
> makes that argument appear NOT to be missing.  But an attempt to
> evaluate it fails because the local variable `n' hasn't been defined
> yet.
> 
> The following debugging snippets, using trace on the method for
> "numeric", show what's happening.  But as to why, we need some expert
> help! (Luke?)

We need a bit more info transferred across from the generic and we
need to reset the environments of the promises for missing arguments.
I'll look into it.

luke

-- 
Luke Tierney
University of Iowa                  Phone:             319-335-3386
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   Actuarial Science
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