R help - Feb 2010 - The 'variables' attribute of terms()

I got the following output when I try the code at the end.
> str(attr(terms1, 'variables'))
 language list(skips, Panel, Opening)
> class(attr(terms1, 'variables'))
[1] "call"

I checked ?call, where 'call' is a function. Could somebody let me
know what a 'call' class is and what 'language' is?

##########
form1=skips ~ Panel * Opening
terms1=terms(form1)
str(attr(terms1, 'variables'))
class(attr(terms1, 'variables'))

bluesky315 at gmail.com wrote:
> I got the following output when I try the code at the end.
> 
>> str(attr(terms1, 'variables'))
>  language list(skips, Panel, Opening)
>> class(attr(terms1, 'variables'))
> [1] "call"
> 
> I checked ?call, where 'call' is a function. Could somebody let me
> know what a 'call' class is and what 'language' is?
> 
See Chapter 2 in the R Language Definition manual.

  -Peter Ehlers
> ##########
> form1=skips ~ Panel * Opening
> terms1=terms(form1)
> str(attr(terms1, 'variables'))
> class(attr(terms1, 'variables'))
> 
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> 
-- 
Peter Ehlers
University of Calgary