title: How many classes should a programmer put in one file?
body: <p>In your object-oriented language, what guidelines do you follow for grouping classes into a single file? Do you always give each class a seperate file? Do you put tightly coupled classes together? Have you ever specified a couple of implementations of an interface in one file? Do you do it based on how many lines of code the implementation might be or how "cluttered" it might look to the user of the class? Or would the user prefer to have everything on one place?</p>