2.7 KiB
Anki: Emacs
The overview of buffers
Front
What is a buffer?
Back
A buffer is anything that Emacs displays.
It usually display file contents among other examples with butterfly, doctor, or the starting buffer when you first open Emacs.
While buffers usually have an associated file path, a buffer doesn't need one. This is one of the concepts that is applied to other text editors (Vim, Atom, Visual Studio Code).
The basics of modes
Front
What is a mode?
Back
A mode is set of behavior quite similar to Vim modes.
Emacs further divides modes into two.
Major modes are Emacs' way of supporting programming languages and file formats.
Programming language support usually comes in major mode — e.g., R-mode for R files, python-mode for Python scripts, org-mode for Org mode documents.
Think of them as an equivalent to Vim's filetype.
Only one major mode can be activated in one buffer at a time and all buffers have a major mode.
Minor modes usually contain little behavioral changes that improve the editing experience. When enabled, some of them are global modes — affecting every buffer in your session. Others are only buffer-local — affecting only the buffer when you activated the mode. Unlike major modes, multiple minor modes can be enabled at any given time.
Eagle's eye view of a window
Front
What is a window?
Back
A window is where the buffers are being displayed. One window can display all buffers but only one at a time. To display two buffers at a single time, just add another window.
All windows display the same buffer; if the buffer is modified in one of the window, it will show the changes in all windows.
Point and marker
Front
What is a point and a marker?
Back
A point is the current location of the cursor in the buffer.
You can get the point with point function.
Often helpful for interacting with buffers.
A marker is another point in the buffer. It is usually found when interacting with regions when asked for the two points (i.e., the beginning and the ending position). Furthermore, a marker can be used to save locations and jump back to that marker when asked.