process PIVOT_WIDER{
    input: path(tsv)
    output: path("wider.tsv"), emit: tsv
    script:
    """
    csvtk spread -t -k 2 -v 3 -H ${tsv} > wider.tsv
    """
}


workflow {
    ch_rows= channel.fromList([["A","V1",1],["A","V2",2],["B","V1",3],["B","V2",4]])
            .view()
            .map{s,c,v->"${s}\t${c}\t${v}"}.view()

    ch_narrow=ch_rows.collectFile(name:"test.tsv",newLine:true).view()
    PIVOT_WIDER(ch_narrow).view()
}