# Stable Element Hierarchy

> The requirement that the set of element types stay fixed so new operations can be added over them.

Record: `lex:stable-element-hierarchy`
Kind: constraint
Layer: [Design Patterns Core](https://banes-lab.com/records/layer/design-patterns-core.md)
Canonical: https://banes-lab.com/ontology/lexicon#lex-stable-element-hierarchy

## category

- [Behavioral Patterns](https://banes-lab.com/records/lex-category/behavioral-patterns.md)

## referenced-by

- [Visitor Pattern](https://banes-lab.com/records/arch/visitor-pattern.md)