1.

Load a document from the current io stream.

File.open( 'animals.yaml' ) { |yf| YAML::load( yf ) }
   #=> ['badger', 'elephant', 'tiger']


example：

require 'yaml'
yml = YAML::load(File.open('t.yml'))
p yml  

Can also load from a string.

YAML.load( "--- :locked" )
   #=> :locked

2.

Load a document from the file located at filepath.

YAML.load_file( 'animals.yaml' )
   #=> ['badger', 'elephant', 'tiger']

参考链接：http://www.ruby-doc.org/stdlib-1.8.7/libdoc/yaml/rdoc/YAML.html