> But what happens when new requirements come in for just one of the things?
I guess it could happen, but that depends on your mental model when coding - if you're just pattern matching similar chunks of code (which are not being used in a semantically identical way) then all bets are off, although that seems a very alien concept of how someone might code.
OTOH, if you have a higher level mental model of what you are doing then it's not a matter of "this looks like common code" but rather "i need to do the exact same operation" (same inputs/outputs/semantics) here. Maybe I'm expressing it poorly, but I can't recall ever having to fork a function because requirements at two call sites just diverged.
I guess it could happen, but that depends on your mental model when coding - if you're just pattern matching similar chunks of code (which are not being used in a semantically identical way) then all bets are off, although that seems a very alien concept of how someone might code.
OTOH, if you have a higher level mental model of what you are doing then it's not a matter of "this looks like common code" but rather "i need to do the exact same operation" (same inputs/outputs/semantics) here. Maybe I'm expressing it poorly, but I can't recall ever having to fork a function because requirements at two call sites just diverged.