> I think the right answer _is_ to export the lazy data; the question is how to
> do it. There's nothing particularly strange about exporting non-functions
> ("letters" would be an example, save for the special status of package:base).
> If you attach the package, the lazyloaded data appear in the same environment
> as the exported function so they are de facto already in the namespace for
> the purposes of library() and `::`. So I agree, something like exportData()
> would be useful. (Or some other mechanism. You might want to be able to
> export data selectively.)
I don't think lazyloaded data are in the same environment as exported
functions - getExportedValue() (called by ::) looks first in the
"exports" namespace, then in the "lazydata" namespace:
function (ns, name)
{
getInternalExportName <- function(name, ns) {
exports <- getNamespaceInfo(ns, "exports")
if (exists(name, envir = exports, inherits = FALSE))
get(get(name, envir = exports, inherits = FALSE),
envir = ns)
else {
ld <- getNamespaceInfo(ns, "lazydata")
if (exists(name, envir = ld, inherits = FALSE))
get(name, envir = ld, inherits = FALSE)
else stop(gettextf("'%s' is not an exported object from
'namespace:%s'",
name, getNamespaceName(ns)), call. = FALSE, domain = NA)
}
}
ns <- asNamespace(ns)
if (isBaseNamespace(ns))
get(name, envir = ns, inherits = FALSE)
else getInternalExportName(name, ns)
}
(But maybe you just meant the library() and :: behaves as is lazydata
and exports were the same thing)
Hadley
--
http://had.co.nz/
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