lib/ddata.js
function classes (options) {
  options.hash.kind = 'class'
  return handlebars.helpers.each(_identifiers(options), options)
}
function classes (options) {
  options.hash.kind = 'class'
  return handlebars.helpers.each(_identifiers(options), options)
}
function classes ( options ) { options . hash . kind = 'class' return handlebars . helpers . each ( _identifiers ( options ) , options ) }
render the block for each class
@static
@category Block helper: selector
render the block for each class