[Rd] What is pairlist in R-ints.pdf?

Simon Urbanek simon.urbanek at r-project.org
Wed Mar 3 17:49:50 CET 2010

On Mar 3, 2010, at 11:29 , blue sky wrote:

> R-ints.pdf mentions pairlist with the reference to mit-scheme.
> However, it is not clear to me what 'pairlist' exactly refers to, as  
> I don't find the definition for it. Does a 'pairlist' in R  
> equivalent to a pair or a list (which is essentially a pair whose  
> cdr is a list) in mit-scheme?

pairlist is short for "dotted pair list" (see ?pairlist) which is a  
syntax for specifying linked lists as ( CAR . CDR ). Since the term  
"list" has a different meaning in R, using just "list" would be  
ambiguous (in the current R lists are implemented as generic vectors,  
not as linked lists).


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