The R Project SVN – R – Diff – /trunk/src/library/base/man/UseMethod.Rd



  their values will be promises to evaluate their name in the current
  method and environment.  Any named arguments matched to \code{\dots}
  are handled specially: they either replace existing arguments of the
  same name or are appended to the argument list.  They are passed on as
  the promise that was supplied as an argument to the current
  environment.  (S does this differently!)  If they have been evaluated
  in the current (or a previous environment) they remain evaluated.
  (This is a complex area, and subject to change: see the draft
  \sQuote{R Language Definition}.)
 
  The search for methods for \code{NextMethod} is slightly different
  from that for \code{UseMethod}.   Finding no \code{fun.default} is not
  necessarily an error, as the search continues to the generic
  itself.  This is to pick up an \link{internal generic} like \code{[}
  which has no separate default method, and succeeds only if the generic
  is a \link{primitive} function or a wrapper for a
  \code{\link{.Internal}} function of the same name.  (When a primitive
  is called as the default method, argument matching may not work as
  described above due to the different semantics of primitives.)

The R Project SVN R

(root)/trunk/src/library/base/man/UseMethod.Rd @ 63243 – Rev 51271 → 55555

Rev 51271		Rev 55555
Line 104...		Line 104...
104	`their values will be promises to evaluate their name in the current`	104	`their values will be promises to evaluate their name in the current`
105	`method and environment. Any named arguments matched to \code{\dots}`	105	`method and environment. Any named arguments matched to \code{\dots}`
106	`are handled specially: they either replace existing arguments of the`	106	`are handled specially: they either replace existing arguments of the`
107	`same name or are appended to the argument list. They are passed on as`	107	`same name or are appended to the argument list. They are passed on as`
108	`the promise that was supplied as an argument to the current`	108	`the promise that was supplied as an argument to the current`
109	`environment. (S does this differently!) If they have been evaluated`	109	`environment. (S does this differently!) If they have been evaluated`
110	`in the current (or a previous environment) they remain evaluated.`	110	`in the current (or a previous environment) they remain evaluated.`
111	`(This is a complex area, and subject to change: see the draft`	111	`(This is a complex area, and subject to change: see the draft`
112	`\sQuote{R Language Definition}.)`	112	`\sQuote{R Language Definition}.)`
113		113
114	`The search for methods for \code{NextMethod} is slightly different`	114	`The search for methods for \code{NextMethod} is slightly different`
115	`from that for \code{UseMethod}. Finding no \code{fun.default} is not`	115	`from that for \code{UseMethod}. Finding no \code{fun.default} is not`
116	`necessarily an error, as the search continues to the generic`	116	`necessarily an error, as the search continues to the generic`
117	`itself. This is to pick up an \link{internal generic} like \code{[}`	117	`itself. This is to pick up an \link{internal generic} like \code{[}`
118	`which has no separate default method, and succeeds only if the generic`	118	`which has no separate default method, and succeeds only if the generic`
119	`is a \link{primitive} function or a wrapper for a`	119	`is a \link{primitive} function or a wrapper for a`
120	`\code{\link{.Internal}} function of the same name. (When a primitive`	120	`\code{\link{.Internal}} function of the same name. (When a primitive`
121	`is called as the default method, argument matching may not work as`	121	`is called as the default method, argument matching may not work as`
122	`described above due to the different semantics of primitives.)`	122	`described above due to the different semantics of primitives.)`