iphone: Does #freeze have a use other than preventing modification?

vendredi 31 juillet 2015

Ruby's standard uri library has many uses of freeze on components which either can't be modified, or where modification will cause no harm:

  user, password = ui.split(':'.freeze, 2)     # from generic.rb

String#split won't modify its arguments, and even if it did, the code would work properly (Ruby will use a new instance of ':' on the next call).

Here are some more uses of freeze on objects that can't change (these are all from generic.rb)

 if @scheme && @scheme != "ftp".freeze 
 v.delete!("\t\r\n".freeze)
 str << ':'.freeze

Why are there so many instances of seemingly needless calls to #freeze? Does #freeze have a use beyond preventing modification of its receiver?

iphone