(expand t "${FOO} ${BAR}")を (format t "~A ~A" FOO BAR)に変換するマクロ

expand.lisp

(ql:quickload :cl-ppcre)

(defpackage :expand
  (:use :cl :ppcre))

(in-package :expand)

(defconstant +regex+ "\\$\\{(.*?)\\}")

(defun expand-string (string)
  (regex-replace-all +regex+ string "~A"))

(defun expand-args (string)
  (let ((args nil))
	(do-register-groups (arg)
		(+regex+ string (nreverse args))
	  (push (read-from-string arg) args))))

(defmacro expand (stream string)
  `(format ,stream ,(expand-string string) ,@(expand-args string)))