code: function( routine ) {
      var it = this
      var routine = Array.isArray( routine )
        ? routine
        : this.routine
  
      routine
      .forEach(function( method ) {
        if (
           typeof method === 'string' &&
           typeof it[ method ] === 'function'
        ) {
          it[ method ]()
        } else if (
          Array.isArray( method ) &&
          typeof it[ method[0] ] === 'function'
        ) {
          it[ method.shift() ].apply( it, method )
        }
      })
      return this
    }
docs: Note that the routine set up here will execute only once. The method won't alter the routine in the instance or in the prototype chain.