Method: DataMapper::Model#first

Defined in:
lib/dm-core/model.rb

#first(*args) ⇒ Resource, Collection

Return the first Resource or the first N Resources for the Model with an optional query

When there are no arguments, return the first Resource in the Model. When the first argument is an Integer, return a Collection containing the first N Resources. When the last (optional) argument is a Hash scope the results to the query.

Parameters:

  • limit (Integer) —

    (optional) limit the returned Collection to a specific number of entries

  • query (Hash) —

    (optional) scope the returned Resource or Collection to the supplied query

Returns:

  • (Resource, Collection) —

    The first resource in the entries of this collection, or a new collection whose query has been merged



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# File 'lib/dm-core/model.rb', line 363

def first(*args)
  first_arg = args.first
  last_arg  = args.last

  limit_specified = first_arg.kind_of?(Integer)
  with_query      = (last_arg.kind_of?(Hash) && !last_arg.empty?) || last_arg.kind_of?(Query)

  limit = limit_specified ? first_arg : 1
  query = with_query      ? last_arg  : {}

  query = self.query.slice(0, limit).update(query)

  if limit_specified
    all(query)
  else
    query.repository.read(query).first
  end
end