# alist-let -- or maybe, plist?
=>gemini://siiky.srht.site/scheme/alist-let.gmi
@silky offers a let-like macro for binding variables based on an alist

Firstly, I am a Common Lisper and know very little Scheme.

First question: what is the purpose of alist-let?  As I understand it (confusedly scanning the code and comments), you can bind symbols specified as keys to their corresponding values.  If you don't know ahead-of-time what the symbol names are, you cannot use them in the body of the let, unless you somehow define local macros that contain those symbol-names...  Otherwise, it's just let with a weirder syntax...

In Common Lisp we have another basic kind of a list, a PLIST, which takes a little more space but is a pretty generic datastructure.  An alist '((a . 1)(b . 2)(c . 3)) may be converted to a plist `((a 1)(b 2)(c 3))...

The great thing about plists is that plists are used to represent parameters to the let form!

A let expression like (let ((a 1)(b 2)(c 3)) ...) already has a plist inside.

It is trivial to construct a macro that splices a plist into a let form:
```
(defmacro plist-let (plist body)
  `(let ,plist
    ,&body))
```

Not very useful, as it is a tautology for the let macro in the first place!

Now if you were to try to splice in an alist from some variable containing a plist, making it a compile-time macro that generates a binding, ok, but again, how would you know the names of the bound symbols?

And if it is entirely dynamic, binding things at runtime, even more so?

I am clearly missing the purpose and a use-case for doing this... A reply would be appreciated.

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