API Stability and Public Object Contracts

Source-derived companion to gp3ml 0.3.0 vignette api-stability-contracts.Rmd. R code blocks are omitted here; the Python companion script is under examples/api-stability-contracts.py.

Why an explicit contract layer?

gp3ml distinguishes the public API established by version 0.2.0 from new development APIs. Stable exported names and registered public S3 classes should not silently disappear or change meaning within the 0.2.x line.

Audit the currently loaded package

A failure indicates removal of an established export or registered public class. An undeclared export is reviewable rather than silently accepted.

Inspect an object schema

The contract policy is additive: established named components retain their meaning, while compatible additions remain possible.