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Comment by math-dev | Hacker News Reader

most of it should work in elisp, note that elisp and common lisp have different semantics for IF.

you might find some variances later on. also elisp doesn’t have as nice a debugging environment as SLIME so I’d honestly recommend just setting up common lisp

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As far as I can tell, any Elisp if-form that is also a valid Common Lisp if-form has the same semantics; but Elisp allows more than one else-form in its syntax, with additional semantics.

It's something like:

  (defmacro elisp-if (expr then &rest elses)
    `(cond (,expr ,then) (t ,@elses)))

Whereas the regular if is like:

  (defmacro cl-if (expr then &optional else)
    `(cond (,expr ,then) (t ,else)))

In a book that uses Common Lisp, you shouldn't see an if-form that isn't Elisp-compatible.

Oh yes you are 100% right, I just had a brain fart. Thanks for correcting

What does “IF” stand for in your comment?

Are you referring to the IF expression or something different?

ignore me, read the comments above

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