Evaluate a closure in a subprocess?

[Klaus-Dieter Bauer <bauer.klaus.dieter@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 1143 bytes --]

Hello!

Currently `lambda' forms evaluate to a `closure' form in lexical
environments, where the first element after the 'closure symbol represents
the lexical environment.

The documentation clearly states that this form shouldn't be relied on, so
e.g. extracting the lexical environment from the closure form is not
future-proof (i.e. using (cadr (lambda ())) as an equivalent to python's
locals() function).

However, the current implementation also allows passing a closure, or even
its byte-code representation, as a string to a different emacs process and
evaluate it there, preserving the values of the captured lexical
environment, e.g.

    (call-process "emacs" nil (current-buffer) nil "--batch" "--eval"
      (format "(print (funcall (quote %S)))"
        (let ((lp load-path))
          (lambda () lp))))

I currently use a similar construct for compiling emacs lisp files in a
clean emacs session (since a long-running session may contain artifacts
that mask or cause errors).

So I was wondering if this is an intended behaviour or also a side-effect
of the current implementation that may change at any time.


regards, Klaus

[-- Attachment #2: Type: text/html, Size: 1489 bytes --]