No formal validation; it relies on naming conventions (e.g., generic.class ). 2. S4: The Rigorous Contract
Managing stateful objects (like database connections, caches, or GUI widgets) and avoiding R’s usual copy-on-modify behavior. Advanced Object-Oriented Programming in R: Stat...
Encapsulation (private vs. public fields); reference semantics (modify objects in-place); method chaining. No formal validation; it relies on naming conventions (e
Methods belong to generic functions , not the objects themselves. When you call plot(x) , R looks at the class of x and decides which plot method to run. Encapsulation (private vs
S4 is a more formal version of S3, requiring explicit class definitions with "slots" and typed data.
Requires an external dependency; can lead to "non-idiomatic" R code if overused. 4. Reference Classes (RC): The Internal Alternative
R6 (via the R6 package ) provides "classical" OOP similar to Java or C++.