As you hint at in your last paragraph, it’s probably hard to come up with a blog-sized example for any programming technique. If 10-15 lines were really the ext

As you hint at in your last paragraph, it’s probably hard to come up with a blog-sized example for any programming technique. If 10-15 lines were really the extent our scope, we probably wouldn’t need anything more advanced than assembler. Some amount of imagination is necessary to consider whether an idea is useful in production code, so we all have different examples in mind. Personally, I’ve had cases where three or four places had to be kept in sync, and the list was changing frequently enough that something like this became useful. Even then, it’s still a judgement call whether code generation or (if available) macros are worth the complexity. The decision might also heavily depend on the experience of the team.