https://github.com/Inaimathi/cl-mop.git
git clone 'https://github.com/Inaimathi/cl-mop.git'
(ql:quickload :cl-mop)
The goal of this library is to provide portable Common Lisp facilities for working with CLOS instances. This first release is minimal because I'm following my usual MO of only implementing things as I need them. There is therefore no call for me to go beyond slot-names, map-slots, shallow-copy and deep-copy yet (and I've used deep-copy in exactly one place so far, so be wary of that one; the others have been at least slightly battle-tested).
In theory, it supports CMUCL, Lispworks, SBCL, Allegro CL, GNU Clisp and OpenMCL with native threads. Really, I've only deployed it with SBCL and did some cursory testing with GNU Clisp. If someone tries it out extensively elsewhere, let me know. As always, patches welcome for CLs not on that list.
All of the exported symbols designate methods and not functions. While I've found the defaults published here to be useful and adequate, there are a lot of crazy things you can do with CLOS that I don't even try to account for. If you have special cases on hand, you can easily define your own methods for those and carry on as normal where cl-mop is sufficient.
In addition to these symbols, cl-mop also re-exports class-slots and slot-definition-name. These functions are imported in a portable fashion which accounts for the different providing packages accross different CL implementations.
Designates two methods; one acting on classes and one acting on instances. In both cases, it returns a list of symbols designating the slot-names of the argument.
Takes a function and an instance, and returns the sequence resulting from running the function on (slot-name slot-value) over each bound slot in an instance. It silently ignores unbound slots, you won't even get a NIL in the resulting list.
Takes an instance and returns the alist of ((slot-name . value) ...) for all bound slots. The trivial application of map-slots, included because I found myself using it quite often.
Takes a CLOS instance and returns a shallow copy of it. I've found this useful in a bunch of places where I really want a copy of an existing instance with one or two slots changed (but don't want to destructively modify the underlying instance).
Takes a CLOS instance and returns a deep copy of it. That is, it allocates a new instance, then deep-copies each slot. USE CAUTION Like I said, I use this in exactly one place, and the only reason shallow-copy won't do there is that one of the slots is a vector I need to change (doing this to a shallow copy would change both the copy and the original). It works in that one use case, but I wouldn't count on it if I was doing something much crazier.
This library is hereby released for public consumption under the Expat license, reproduced below and in a separate LICENSE file.
Copyright (c) 2012 Inaimathi
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The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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