`addattr` <- function(x,...) UseMethod("addattr")

#' @exportS3Method
`addattr.lvmfit` <- function(x,...) addattr(Model(x),...)

#' @exportS3Method
`addattr.lvm` <- function(x, attr, var=NULL, val=TRUE, fun=graph::nodeRenderInfo,debug=FALSE,...) {
    if (!is.null(var)) {
        Graph(x) <- addattr(Graph(x), attr=attr, var=var, val=val, fun=fun, debug=debug)
        return(x)
    } else {
        addattr(Graph(x), attr=attr, var=var, val=val, fun=fun)
    }
}

#' @exportS3Method
`addattr.graphNEL` <- function(x, attr, var=NULL, val=TRUE,fun="graph::nodeRenderInfo",debug=FALSE,...) {
    if (is.null(var)) {
        ff <- strsplit(fun,"::")[[1]]
        if (length(ff)>1) {
            ff <- getFromNamespace(ff[2],ff[1])
        }
        f <- do.call(ff,list(x))
        if (is.null(val) || !is.logical(f[[attr]]))
            attrvar <- f[[attr]]
        else
            attrvar <- names(f[[attr]])[which(val==f[[attr]])]
        return(attrvar)
    }
    if (is.character(val))
        myexpr <- paste0("list(",attr,"=c(", paste0("\"",var,"\"=\"",val,"\"" , collapse=", "), "))")
    else
        myexpr <- paste0("list(",attr,"=c(", paste0("\"",var,"\"=",val, collapse=", "), "))")
    Debug(list("str=",myexpr),debug)
    eval(parse(text=paste0(fun,"(x) <- ",myexpr)))
    return(x)
}

