old_contents: module.exports = {
    aggregate:    require('./Aggregate'),
    bin:          require('./Bin'),
    cross:        require('./Cross'),
    countpattern: require('./CountPattern'),
    linkpath:     require('./LinkPath'),
    facet:        require('./Facet'),
    filter:       require('./Filter'),
    fold:         require('./Fold'),
    force:        require('./Force'),
    formula:      require('./Formula'),
    geo:          require('./Geo'),
    geopath:      require('./GeoPath'),
    hierarchy:    require('./Hierarchy'),
    impute:       require('./Impute'),
    lookup:       require('./Lookup'),
    pie:          require('./Pie'),
    sort:         require('./Sort'),
    stack:        require('./Stack'),
    treeify:      require('./Treeify'),
    treemap:      require('./Treemap'),
    voronoi:      require('./Voronoi'),
    wordcloud:    require('./Wordcloud')
  };
new_contents: module.exports = {
    aggregate:    require('./Aggregate'),
    bin:          require('./Bin'),
    cross:        require('./Cross'),
    countpattern: require('./CountPattern'),
    linkpath:     require('./LinkPath'),
    facet:        require('./Facet'),
    filter:       require('./Filter'),
    fold:         require('./Fold'),
    force:        require('./Force'),
    formula:      require('./Formula'),
    geo:          require('./Geo'),
    geopath:      require('./GeoPath'),
    hierarchy:    require('./Hierarchy'),
    impute:       require('./Impute'),
    lookup:       require('./Lookup'),
    pie:          require('./Pie'),
    rank:         require('./Rank'),
    sort:         require('./Sort'),
    stack:        require('./Stack'),
    treeify:      require('./Treeify'),
    treemap:      require('./Treemap'),
    voronoi:      require('./Voronoi'),
    wordcloud:    require('./Wordcloud')
  };
subject: Include Rank in transforms registry.