.BasicFunsList            package:methods            R Documentation

List of Builtin and Special Functions

Description:

     A named list providing instructions for turning builtin and
     special functions into generic functions.

     Functions in R that are defined as '.Primitive(<name>)' are not
     suitable for formal methods, because they lack the basic
     reflectance property.  You can't find the argument list for these
     functions by examining the function object itself.

     Future versions of R may fix this by attaching a formal argument
     list to the corresponding function.  While generally the names of
     arguments are not checked by the internal code implementing the
     function, the number of arguments frequently is.

     In any case, some definition of a formal argument list is needed
     if users are to define methods for these functions.  In
     particular, if methods are to be merged from multiple packages,
     the different sets of methods need to agree on the formal
     arguments.

     In the absence of reflectance, this list provides the relevant
     information  via a dummy function associated with each of the
     known specials for which methods are allowed.

     At the same, the list flags those specials for which methods are
     meaningless (e.g., 'for') or just a very bad idea (e.g.,
     '.Primitive').

     A generic function created via 'setMethod', for example, for one
     of these special functions will have the argument list from
     '.BasicFunsList'.  If no entry exists, the argument list '(x,
     ...)'  is assumed.

