Add a variable to a class instance at runtime: Difference between revisions

{{task|Object oriented}}

This demonstrates how to dynamically add variables to a class instance at runtime. This is useful when the methods/variables are based on a data file that isn't available until runtime. Hal Fulton gives an example of creating an OO CSV parser at [http://www.devsource.com/article2/0,1759,1928562,00.asp An Exercise in Metaprogramming with Ruby]. This is referred to as "monkeypatching" by Pythonistas and some others. It's possible in most '''dynamic''' OO languages such as Python, Ruby, and Smalltalk.