\name{releaseDate}
\alias{releaseDate}
\title{A method to return the release date of the PSI-MI 2.5
       XML file}
\description{
The \code{releaseDate} function takes an intactInteraction class and
returns the data when the XML file is repacked and released from 
IntAct. This serves as a proxy for versioning.
}
\usage{
releaseDate(x)
}
\arguments{
  \item{x}{A S4 object of type intactInteraction}
  }
\value{
A character. The release date.}
\references{The IntAct Database \url{http://www.ebi.ac.uk/intact/site/contents/downloads.jsf}.}
\author{T Chiang}

\seealso{\code{\intactInteraction-class}}

\examples{
# parse complex data
}
\keyword{ models }