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What are the major differences between Emacs Lisp and Common Lisp?


I want to learn the lisp language, since my editor is emacs, I prefer emacs lisp.

Can anyone give me some suggestions to learn lisp, emacs lisp, or common lisp?

What are the major differences between those two?


Solution

  • There's quite a bit of crossover, especially at the beginner level, so whichever you start with will mostly transfer to the other.

    Some of the major differences:

    • ELisp traditionally used dynamic scoping rules; Common Lisp uses lexical scoping rules. With dynamic scoping, a function can access local variables declared in calling functions and has generally fallen out of favor. Starting with Emacs 24, Emacs allows optional lexical scoping on a file-by-file basis (and all files in the core distribution are progressively being converted).

    • Dynamically scoped ELisp doesn't have closures, which makes composing functions and currying difficult. There's a apply-partially function that works similarly to currying. Note that the lexical-let form introduced in Emacs 24 makes it possible to produce closures via lexical scoping.

    • Much of the Common Lisp library that has been built up over time isn't available in elisp. A subset is provided by the elisp cl package

    • elisp doesn't do tail-call optimization.