![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
Code reuse
Mar. 25th, 2019 02:32 amFrom 11 years of maintaining my own codebase I learned that reusing fields is a bad idea that leads to poor code maintainability.
If unrelated methods use the same fields, then graph of field references start looking like a maze that is very hard to understand.
If "UserId" field is called by 19 methods from at least 2 distinct logical groups, then it takes long time to find out if we still need to load UserId from database record in JobAlertRequest().
If count of UserId references was much lower, then such review would take much less time.
Reusing fields (and local variables) is, generally, bad for maintenance.
But reusing methods is, generally, good for maintenance: if we fix bugs in a reused method - all places that use functionality are getting fixed.
If unrelated methods use the same fields, then graph of field references start looking like a maze that is very hard to understand.
If "UserId" field is called by 19 methods from at least 2 distinct logical groups, then it takes long time to find out if we still need to load UserId from database record in JobAlertRequest().
If count of UserId references was much lower, then such review would take much less time.
Reusing fields (and local variables) is, generally, bad for maintenance.
But reusing methods is, generally, good for maintenance: if we fix bugs in a reused method - all places that use functionality are getting fixed.
