this post was submitted on 17 Oct 2023
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It's symbols not strings are fundamental data type, an insight from read. (alien.top)
submitted 1 year ago by AbstProcDo@alien.top to c/emacs@communick.news
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In elisp, symbols serve as fundamental data structures that are more foundational compared to strings. This distinction often caused confusion for me until my encounter with the read function.

 ~ $ (type-of (read))
 symbol

The fact that the read function yields symbols instead of strings from user-input was a delightful revelation. This discovery convinces me that the fundamental nature of symbols in elisp when compared to strings.

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[–] AbstProcDo@alien.top 1 points 1 year ago (2 children)

Interesting. It’s intelligent capability to discern and identify numbers, strings, and symbols. What I tried is to feed to minibuffer word string.

[–] arthurno1@alien.top 1 points 1 year ago

What I tried is to feed to minibuffer word string.

So you have called:

M-: (type-of (read)) RET string RET?

You have just created a temporary symbol named "string". You can try this to see for yourself:

M-: (symbol-name (type-of (read))) RET

If you want a string object out of "string", you will have to quote it in the minibuffer too:

M-: (type-of (read)) RET "string" RET?

I think you should have not downvoted /u/lispm below (or whomever it was); he has given a few very good questions to get you going on in exploring those things on your own.

[–] 7890yuiop@alien.top 1 points 1 year ago 
(type-of (read "foo"))
symbol

(type-of (read "\"foo\""))
string

(type-of (read "42"))
integer

(type-of (read "[42]"))
vector

(type-of (read "(42)"))
cons

Etc, etc...

The lisp reader reads text and it produces lisp objects of various types (which might later be evaluated as code).