Develop one project file all at once or incrementally?

Question

Programming

The application has many files. How to fill them with code?
1. Open files one by one, fill 100% with the planned functionality (various types).
2. Open files, fill them with N% functionality, then open the same file a day later, fill in another N% functionality, and another day later? In the interval between filling, other files are filled.
That is, to fill the code through (everything in a row), or according to the logic of the modules?

Answer 1

What is this question anyway? I did not understand anything, you are like a painter-painter. Either paint on one wall, or all at once. For programming, this is nonsense.
My answer to you is: You should use version control, and each time the "code state" should be working. That. no matter how you develop, it is important that the changes do not break the previous state of the code. Those. you gradually move from complete 0 to full functionality.