Functions are the first tier of organization Should have as few levels of indent as possible Functions should be well named and should be organized into well named classes within well named namespaces
Functions should be 4,6 lines.
what does one thing means ?
If your function is composed of many different sections then is clearly doing more than one thing.
If the function manipulates more than one level of abstraction is doing more than one thing.
But abstraction levels are fuzzy, this fuzziness is undesirable.
We want an un ambiguos way to tell that a function is doing just one thing.
This way is continue to extract functions until you cannot extract any more
When you have a function that can be divided into several functional areas and you have variables that are used by all those functional areas then you have Class Since a Class is a group of functions that uses a common set of variables.
I didn’t have time to make it smaller It takes time to eliminate redundancy It takes time to organise our thoughts It takes time to make things small Leaving something big is irresponsable, careless, it skip the breaking down your thoughts and explain them at your readers You might be saving yourself a little bit of time but you are costing everyone else a lot of time. Or maybe yourself will have to face same code in future and will have to break down your thoughts and try to understand it spending time doing this. So leaving a function long at the end is going to cost a lot of time and effort.
That scope is divided into different sections of functionality Usually seen as mayor indentations Those different sections communicate with each other using variables that are local to the entire scope So what do you have when you got a set of variables in a long scope accessed by many different segments of functionality ? A CLASS!!