require
require(p1)
private
Loads the given name, returning true if successful and false if the feature is already loaded.
If the filename does not resolve to an absolute path, it will be searched for in the directories listed in $LOAD_PATH ($:).
If the filename has the extension “.rb”, it is loaded as a source file; if the extension is “.so”, “.o”, or “.dll”, or the default shared library extension on the current platform, Ruby loads the shared library as a Ruby extension. Otherwise, Ruby tries adding “.rb”, “.so”, and so on to the name until found. If the file named cannot be found, a LoadError will be raised.
For Ruby extensions the filename given may use any shared library extension. For example, on Linux the socket extension is “socket.so” and require ‘socket.dll’ will load the socket extension.
The absolute path of the loaded file is added to $LOADED_FEATURES ($“). A file will not be loaded again if its path already appears in $”. For example, require ‘a’; require ‘./a’ will not load a.rb again.
require "my-library.rb" require "db-driver"
Any constants or globals within the loaded source file will be available in the calling program’s global namespace. However, local variables will not be propagated to the loading environment.