How to copy and cut multiple lines in Emacs correctly?

Question

I have researched it. Most post said this way:

C-SPC C-n M-w

It works. But in my case. It only copied a block where the cursor moved. Not the whole lines area I want.

For example, the source below:

1 def hi():
2    print("hi")
3 .  print("hi")
4    print("hi")
----------col:16

The operations I did:

1. At the beginning of line 1, click C-x SPC (Because I'm using macOS so C-SPC not work, the keys are conflict)
2. Move down using C-n until line 4
3. Click C-e to the end of the last line ensure to get all the area I want
4. Finally click M-w to copy them.
5. Paste them at other area by C-y. The line 1 likes def hi():_____ with visible space

I can copy the content until col 16, but without the area afterward. So if I paste the content somewhere, the layout went bad.

---

Key conflict

Answer 1

The problem is that C-x SPC does something different from C-SPC - it is bound to rectangle-mark-mode, which causes the behaviour you're seeing: the selection is rectangular, rather than a range of text.

One thing you can do is using C-@ instead of C-SPC - both are bound to set-mark-command by default. Or you could find some other key binding that's convenient for you, and set it in your Emacs init file. For example, use Control-Tab with:

(global-set-key (kbd "C-<tab>") 'set-mark-command)