gitbook/lib/modifiers/summary/index.js

module.exports = {
    insertArticle:      require('./insertArticle'),
    moveArticle:        require('./moveArticle'),
    removeArticle:      require('./removeArticle'),
    unshiftArticle:     require('./unshiftArticle'),

    editPartTitle:      require('./editPartTitle'),
    editArticleTitle:   require('./editArticleTitle')
};