nfunato

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以下の翻訳文は、Felix Winkelmann の Thoughts on Forth Programming 
(http://call-with-current-continuation.org/articles/forth.txt) の
翻訳であり、原著者の許可を得て公開するものです。
                2021-09-01 Nobuhiko FUNATO (nfunato @ acm . org)

更新履歴: 
2021-09-02(rev10): Shiro Kawaiさんにご指摘いただいた誤訳訂正/改善を反映
2021-09-02(rev09): 公開初版
------------------------------------------------------------------

puffnfresh

How do we add extra information to a tree? This has been called [The
AST Typing
Problem](http://blog.ezyang.com/2013/05/the-ast-typing-problem/).

After being hit with this problem in Roy's new type-inference engine,
I tried figuring out how to represent the algorithm. I eventually
realised that it looked like a comonadic operation. Turns out it's
been done before but I couldn't find any complete example.

Below is some literate Haskell to show how to use the Cofree Comonad

kiwanami

;;; direx plugin

(require 'direx)
(require 'direx-project)
(setq direx:leaf-icon "  "
      direx:open-icon "▾ "
      direx:closed-icon "▸ ")

(defun e2wm:def-plugin-direx (frame wm winfo) 
  (let* ((buf (e2wm:history-get-main-buffer))

m2ym

(in-package :cl-user)

(defmacro my-macrolet (&environment env bindings &body body)
  (let* ((local-macros
           (loop for (name lambda-list . body) in bindings
                 for macro-lambda = (sb-cltl2:parse-macro name lambda-list body)
                 for macro-fun = (sb-cltl2:enclose macro-lambda env)
                 collect `(,name ,macro-fun)))
         (new-env (sb-cltl2:augment-environment env :macro local-macros)))
    (sb-cltl2:macroexpand-all `(locally ,@body) new-env)))