It seems like "behavior change" as you use it here implies "has an effect" in the functional programming sense. "Interacts noticeably differently with the outside world".
I would love to see this understanding of "behavior" become more common; it would help us avoid many arguments that amount to violent agreement.
Structure changes are developers' decisions. Behavior changes encapsulate business. We can always change/improve our design, but we cannot change the encapsulated business without customer change requests. So we want to be able to manage development-related decisions without effect encapsulated business. imo That is great support for refactoring and for design evolution.
The phrase "...strive to make as few structure changes irreversible as you can" to me connects perfectly with many techniques we may use to keep structural changes easily reversible: refactoring (a series of small behavior-preserving code transformations) is the first one for me, and more generally speaking a "development by small increments" mindset.
It seems like "behavior change" as you use it here implies "has an effect" in the functional programming sense. "Interacts noticeably differently with the outside world".
I would love to see this understanding of "behavior" become more common; it would help us avoid many arguments that amount to violent agreement.
Hi Kent,
Could we say Behaviour is not reversible because Behaviours produce change? :)
Structure changes are developers' decisions. Behavior changes encapsulate business. We can always change/improve our design, but we cannot change the encapsulated business without customer change requests. So we want to be able to manage development-related decisions without effect encapsulated business. imo That is great support for refactoring and for design evolution.
Great insights Kent, thanks!
The phrase "...strive to make as few structure changes irreversible as you can" to me connects perfectly with many techniques we may use to keep structural changes easily reversible: refactoring (a series of small behavior-preserving code transformations) is the first one for me, and more generally speaking a "development by small increments" mindset.