listDuplicatesProcess <- function(
    src,
    handle.duplicates=c("stop", "keep.original", "keep.first", "keep.last",
        "index.duplicates", "index.all"),
    do.return.flat=TRUE,
    .delim.index="-",
    .delim.path="/",
    ...
){
    .buffer <- new.env()
    
    if(length(handle.duplicates) > 1){
        handle.duplicates <- handle.duplicates[1]
    }
    # FLATTEN
    if(!("FlatList" %in% class(src))){
        src.flat <- flatten(
            src=src, 
            do.index=TRUE, 
            .delim.index=.delim.index,
            .delim.path=.delim.path
        )
    } else {
        src.flat <- src
    }
    # /
    if(!all(src.flat$degree == c(0,0))){
        stop("Flatlist of degree c(0,0) required.")
    }
    .buffer$src.flat <- src.flat
    .buffer$index    <- NULL
    
    idx.dupl <- which(src.flat$index$table$duplicate)
    src.flat.split  <- split(
        .buffer$src.flat$index$table[idx.dupl,], f=.buffer$src.flat$index$table$name[idx.dupl]
    )
    if(length(idx.dupl)){
        if( !is.expression(handle.duplicates)){
            if(handle.duplicates == "stop"){
                stop("Duplicates identified.")
            }
        }     
        JNK <- sapply(src.flat.split, function(x.spl){
            if(!is.expression(handle.duplicates)){
                idx.dupl <- which(.buffer$src.flat$index$table$name %in% 
                    x.spl$name)
                if(handle.duplicates == "index.duplicates"){
                    index.new <- list(.buffer$src.flat$index$table[idx.dupl[-1],])
                    names(index.new) <- unique(x.spl$name)
                    .buffer$index <- c(.buffer$index, index.new)
                    return(NULL)
                }
                if(handle.duplicates == "index.all"){
                    index.new <- list(.buffer$src.flat$index$table[idx.dupl,])
                    names(index.new) <- unique(x.spl$name)
                    .buffer$index <- c(.buffer$index, index.new)
                    return(NULL)
                }
                if(handle.duplicates == "keep.original"){
                    idx.keep <- 1
                    idx.dupl <- idx.dupl[-idx.keep]
                    idx.drop <- which(
                        names(.buffer$src.flat$flat) %in% 
                            .buffer$src.flat$index$table$name[idx.dupl]
                    )[-idx.keep]
                }
                if(handle.duplicates == "keep.first"){
                    idx.keep <- 2
                    idx.dupl <- idx.dupl[-idx.keep]
                    idx.drop <- which(
                        names(.buffer$src.flat$flat) %in% .buffer$src.flat$index$table$name[idx.dupl]
                    )[-idx.keep]
                }
                if(handle.duplicates == "keep.last"){
                    idx.keep <- length(idx.dupl)
                    idx.dupl <- idx.dupl[-idx.keep]
                    idx.drop <- which(
                        names(.buffer$src.flat$flat) %in% .buffer$src.flat$index$table$name[idx.dupl]
                    )
                    idx.drop <- idx.drop[-idx.keep]
                }
            } else {
#handle.duplicates <- expression(.buffer$src.flat$index$table$class == "numeric")
# TODO
# Test more thoroughly.    
                idx.dupl <- which(.buffer$src.flat$index$table$name %in% x.spl$name)
                idx.drop <- which(
                    names(.buffer$src.flat$flat) %in% .buffer$src.flat$index$table$name[idx.dupl]
                )
                idx.expr <- which(eval(handle.duplicates))
                if(!length(idx.expr)){
                    msg <- c(
                        "Duplicate processing criterion could not be matched:",
                        paste("* handle.duplicates: '", handle.duplicates, "'", sep="")
                    )
                    stop(cat(msg, sep="\n"))
                }
                idx.keep <- which(idx.dupl %in% idx.expr)                
                if(!length(idx.keep)){
                    msg <- c(
                        "Duplicate processing criterion could not be matched:",
                        paste("* handle.duplicates: '", handle.duplicates, "'", sep="")
                    )
                    stop(cat(msg, sep="\n"))
                }
                if(length(idx.keep) > 1){
                    msg <- c(
                        "Duplicate processing criterion resulted in multiple matches:",
                        paste("* handle.duplicates: '", handle.duplicates, "'", sep=""),
                        paste("* Matches: ", paste(idx.dupl[idx.keep], collapse=" "), sep="")
                    )
                    stop(cat(msg, sep="\n"))
                }
                idx.dupl <- idx.dupl[-idx.keep] 
                idx.drop <- idx.drop[-idx.keep]
            }
            idx.dupl.1  <- strsplit(
                .buffer$src.flat$index$table$index[idx.dupl], split=.delim.index
            )
            .buffer$counter <- 0            
            idx.dupl.1 <- lapply(idx.dupl.1, function(x){
                idx <- as.numeric(x)
                idx[length(idx)]    <- idx[length(idx)] - .buffer$counter
                .buffer$counter     <- .buffer$counter + 1
                return(idx)
            })   
            JNK <- sapply(idx.dupl.1, function(x.idx){
                .buffer$src.flat$original[[x.idx]] <- NULL
            })
            
            if(length(idx.drop)){
                .buffer$src.flat$flat <- .buffer$src.flat$flat[-idx.drop]
            }
            .buffer$src.flat$index$raw      <- .buffer$src.flat$index$raw[-idx.dupl]
            .buffer$src.flat$index$table    <- .buffer$src.flat$index$table[-idx.dupl,]
            .buffer$src.flat$index$table$duplicate <- FALSE
            rownames(.buffer$src.flat$index$table) <- NULL
            
            # FIND RIGHT BOTTOM LAYER VALUES
            idx.bottom <- which(
                .buffer$src.flat$index$table$is.bottom &
                .buffer$src.flat$index$table$name == unique(x.spl$name)
            )          
            # /
            # UPDATE INDEX IN TABLE 
            idx.index  <- strsplit(
                .buffer$src.flat$index$table$index[idx.bottom], split="-"
            )
            index.new <- sapply(idx.index, function(x){
                x[length(x)] <- 1
                paste(x, collapse=.delim.index)
            })
            .buffer$src.flat$index$table$index[idx.bottom] <<- index.new
            # /
            # UPDATE INDEX IN RAW
            tmp.paths <- unique(.buffer$src.flat$index$table$name[idx.bottom])
            
            JNK <- sapply(seq(along=tmp.paths), function(x){                 
                .buffer$src.flat$index$raw[[tmp.paths[x]]]$index <<- index.new[x] 
            })
            # /
        })
    }  
    
    # RETURN VALUE
    if( handle.duplicates == "index.duplicates" |
        handle.duplicates == "index.all" 
    ){
        out <- .buffer$index
    } else {
        if(do.return.flat){
            out <- .buffer$src.flat       
        } else {
            out <- .buffer$src.flat$original
        }
    }
    # /
    return(out)
}