\name{recodeMissingHandlers}
\alias{recodeMissingHandlers}
\title{Creates a set of recode missing handlers corresponding a coding scheme.}
\description{
  This takes a list of missing handler (\code{originalHandler}) and a
  coding scheme in the style of \code{omitCodeStrings} and produces a
  new list of handlers all with the value of \code{handler} set to
  \sQuote{Recode}.  This can be used in a pretest description file to
  change the coding of missing values.
}
\usage{
recodeMissingHandlers(originalHandlers, codeTable = omitCodeGENASYS)
}
%- maybe also 'usage' for other objects documented here.
\arguments{
  \item{originalHandlers}{A list of \code{MissingCode} objects.}
  \item{codeTable}{A named character vector with the names corresponding
    to the \code{type} fields of the \code{MissingCode} objects and the
    values corresponding to the coding for the missing values.}
}
\details{
  If the data file uses a different coding scheme for missing values
  than the Assessment Model Description expects, then the data needs to
  be recoded.  The StatShop Pretest converter tool will do that
  recoding, but needs a appropriate meta-data in the Pretest Description
  file.  This function produces a new set of \code{MissingCode} options,
  all of type \sQuote{Recode} which does the job.

  The recoding is looked up by the \code{type} field in the
  \code{codeTable} argument.  If no coding is found for a type, then the
  original handler is maintained.
}
\value{
  A list of \code{MissingCode} objects, all of type \sQuote{Recode}, of
  the same length as \code{originalHandlers}.
}
\references{
  \url{http://research.ets.org/~ralmond/StatShop/dataFormats.html}
}
\author{Russell Almond }
\seealso{\code{\link{MissingCode}}, 
         \code{\link{omitCodeStrings}}, \code{\link{xmlMissingCode}}
	 \code{\link{xmlPretestDescription}}
}
\examples{
 roh <- recodeMissingHandlers(defaultMissingCodes)
 recodeMissingHandlers(defaultMissingCodes,omitCode789)

 \dontshow{
 stopifnot(
   length(roh) == length(defaultMissingCodes),
   all(sapply(roh,function(m) m$type) ==
       sapply(defaultMissingCodes,function(m) m$type))
 )
 for (i in 1:length(defaultMissingCodes)) {
   hold <- defaultMissingCodes[[i]]
   hnew <- roh[[i]]
   if (is.na(omitCodeGENASYS[hold$type])) {
      stopifnot(identical(hold,hnew))
   } else {
      stopifnot(hnew$handler == "Recode",
       hnew$newval == omitCodeGENASYS[hold$type])
   }
 }
 }
}
\keyword{manip}% at least one, from doc/KEYWORDS