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}
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}
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\value{
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\value{
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  The \code{\link{environment}} is returned invisibly with a
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  The \code{\link{environment}} is returned invisibly with a
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  \code{"name"} attribute.
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  \code{"name"} attribute.
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}
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}
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\section{Good practice}{
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  \code{attach} has the side effect of altering the search path and this
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  can easily lead to the wrong object of a particular name being found.
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  People do often forget to \code{\link{detach}} databases.
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  In interactive use, \code{\link{with}} is usually preferable to the
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  use of \code{attach}/\code{detach}.
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  In programming, functions should not change the search path unless
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  that is their purpose.  Often \code{\link{with}} can be used within a
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  function, but if not good practice is to
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  \itemize{
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    \item Always use a distinctive \code{name} argument, and
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    \item To immediately follow the \code{attach} call by an
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    \code{\link{on.exit}} call to \code{detach} using the distinctive name.
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  }
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  This ensures that the search path is left unchanged even if the
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  function is interrupted or if code after the \code{attach} call
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  changes the search path.
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}
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\references{
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\references{
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  Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988)
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  Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988)
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  \emph{The New S Language}.
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  \emph{The New S Language}.
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  Wadsworth & Brooks/Cole.
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  Wadsworth & Brooks/Cole.
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}
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}