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  \link{InternalGenerics}).  In particular it will not work inside
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  \link{InternalGenerics}).  In particular it will not work inside
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  anonymous calling functions (e.g., \code{get("print.ts")(AirPassengers)}).
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  anonymous calling functions (e.g., \code{get("print.ts")(AirPassengers)}).
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  Namespaces can register methods for generic functions.  To support
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  Namespaces can register methods for generic functions.  To support
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  this, \code{UseMethod} and \code{NextMethod} search for methods in
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  this, \code{UseMethod} and \code{NextMethod} search for methods in
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  two places: first in the environment in which the generic function
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  two places: in the environment in which the generic function
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  is called, and then in the registration data base for the
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  is called, and in the registration data base for the
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  environment in which the generic is defined (typically a namespace).
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  environment in which the generic is defined (typically a namespace).
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  So methods for a generic function need to be available in the
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  So methods for a generic function need to be available in the
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  environment of the call to the generic, or they must be registered.
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  environment of the call to the generic, or they must be registered.
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  (It does not matter whether they are visible in the environment in
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  (It does not matter whether they are visible in the environment in
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  which the generic is defined.)
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  which the generic is defined.)  As from \R 3.5.0, the registration
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  data base is searched after the top level environment (see
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  \code{\link{topenv}}) of the calling environment (but before the
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  parents of the top level environment).
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}
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}
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\section{Technical Details}{
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\section{Technical Details}{
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  Now for some obscure details that need to appear somewhere.  These
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  Now for some obscure details that need to appear somewhere.  These
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  comments will be slightly different than those in Chambers(1992).
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  comments will be slightly different than those in Chambers(1992).
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  (See also the draft \sQuote{R Language Definition}.)
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  (See also the draft \sQuote{R Language Definition}.)