[R] Completion for custom "$" operator?

[Vitalie S.]

Dear UseRs,

I declared a `$` method for a S4 class. Can I have ab automatic completion  
for this operator in R? Lists and environment objects provide this feature  
by default, but my object is an extension of "function" class which does  
not have subseting defined. How to be?

Thanks for any input.
Vitalie.

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