[R] what can one do with (to) '..." ?

[Carl Witthoft]

I followed a couple threads from the archives and from 
stackoverflow.com, and would like to know: just what is "..."  ?  What I 
mean by this is,for example, from the point of view of a user running a 
function in debug mode,  is "..." an object, or does it exist in the 
current environment as some thingy?

Maybe a better question to ask is: if I were to write some function that 
accepts "..." for its own personal use, how do I access the optional 
arguments?   Do I simply have to do a series of 'match' or 'pmatch'  on 
the output of list(...) , or is there a more direct way to get at the 
variables?

If there is a R programmer's manual that discusses this, I'm happy to 
read that, so just let me know.

thanks
Carl

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