What makes Emacs a great editor for a Lisp programmer?

Question

Whenever I look into an editor for Lisp, inevitably Emacs comes up first. From the perspective of someone who hasn't looked much at Emacs, what makes it great relative to things like Vim, Eclipse, etc.?

Answer 1

The slime Emacs mode interact with an "inferior" lisp for a more better lisp experience: Emacs will ask lisp for:

• completion of identifier
• documentation
• testing your new code
• debugging
• inspecting object.

the fact that Emacs was written by lisp hacker make the part specifically written for lisp particularly well tuned.

Answer 2

Emacs is great for Lisp because Emacs is written in Lisp (mostly). The people who designed and implemented Emacs wanted an editor that was well suited for writing Lisp code.