developers' guide: document features of attach, load, iload, ed, %ed, %edit, edit()
From this sagedevel thread:
By the way, I discovered accidentally that from the command line (not
the notebook) if you type:
sage: ed # or %ed or %edit
then it opens up your favorite editor (whatever is set by the $EDITOR
shell variable). Then in the editor you can type
def FF(x):
long definition here
which would be really annoying
to type on the command line
then save it  it gets written to a temporary file  and the code
gets executed and you have thus redefined FF. Then later you can do
sage: ed FF
and it will let you modify your code. This is an ipython feature, it
seems. Should it be described somewhere in the Sage documentation?
The following commands should at least be documented in the Developers' Guide together with explanation on how to use them for interactive development:
load
 see sage.misc.interpreter
attach  see
sage.misc.interpreter
iload
 see sage.misc.interpreter
ed
%ed
%edit
 see the IPython manual
edit()
 see sage.misc.edit_module.edit
Change History (10)
Summary: 
develoers' guide: document features of attach, load, iload, ed, %ed, %edit, edit() →
developers' guide: document features of attach, load, iload, ed, %ed, %edit, edit()

Description: 
modified (diff)

Milestone: 
sage5.11 →
sage5.12

Milestone: 
sage6.1 →
sage6.2

Milestone: 
sage6.2 →
sage6.3

Milestone: 
sage6.3 →
sage6.4

Some of those commands  the % ones  come from IPython, right? If so, we should find where their documentation is online and link to that, along with some brief descriptions of useful commands. One that I like is
!clear
which simply clears the screen.