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2 points by lojic 5366 days ago | link | parent

Can you summarize the principal changes required to work with an immutable cons ? I guess now that the files are versioned (thanks!) I can just do a diff, but if there are extensive changes, it might cause a Lisp newbie to miss the forest for the trees.

4 points by lojic 5366 days ago | link

In ac.scm

  ;; set a pointer to the cons cell, then dereference it as a pointer,
  ;; and bang the new value in the given offset
Hmm... so the fix was to "cast" the immutable cons cell to a mutable cons cell? Glad it works, but I was kind of hoping to learn that the immutable cons cell thing was workable for Arc. I guess I should read up on the MzScheme decision to make it immutable and see what pros/cons are associated with it.


1 point by soegaard 5365 days ago | link

See Flatt's blog post:

Further discussions can be found in the mail archive.


1 point by vegashacker 5365 days ago | link

Here's a post about it: