How to reference a local variable inside the definition of a function?

Question

Is it possible to reference a local variable inside the definition of a function? Here's an example:

I have an alist text-alist consisting of keys and text snippets. I want each text snippet bound to a key in the prefix map my-text-prefix-map. The code below doesn't work, I guess because when the functions in my-text-prefix-map are run, the value of text is unknown. Is there any way to remedy this?

(mapc (lambda (text)
        (define-key my-text-prefix-map (kbd (car text))
          (lambda ()
            (interactive)
            (insert (cdr text)))))
      text-alist)

Answer 1

You can use backquotes and commas to build functions dynamically:

`(lambda ()
   (interactive)
   (insert ,(cdr text)))

Or you can also enable lexical-binding to make function closures.

More information on Backquotes can be found in Emacs manual.