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+;;; srfi-26.scm --- specializing parameters without currying.
+
+;; Copyright (C) 2002, 2006 Free Software Foundation, Inc.
+;;
+;; This library is free software; you can redistribute it and/or
+;; modify it under the terms of the GNU Lesser General Public
+;; License as published by the Free Software Foundation; either
+;; version 2.1 of the License, or (at your option) any later version.
+;;
+;; This library is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+;; Lesser General Public License for more details.
+;;
+;; You should have received a copy of the GNU Lesser General Public
+;; License along with this library; if not, write to the Free Software
+;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+(define-module (srfi srfi-26)
+ :export (cut cute))
+
+(cond-expand-provide (current-module) '(srfi-26))
+
+(define-macro (cut slot . slots)
+ (let loop ((slots (cons slot slots))
+ (params '())
+ (args '()))
+ (if (null? slots)
+ `(lambda ,(reverse! params) ,(reverse! args))
+ (let ((s (car slots))
+ (rest (cdr slots)))
+ (case s
+ ((<>)
+ (let ((var (gensym)))
+ (loop rest (cons var params) (cons var args))))
+ ((<...>)
+ (if (pair? rest)
+ (error "<...> not on the end of cut expression"))
+ (let ((var (gensym)))
+ `(lambda ,(append! (reverse! params) var)
+ (apply ,@(reverse! (cons var args))))))
+ (else
+ (loop rest params (cons s args))))))))
+
+(define-macro (cute . slots)
+ (let ((temp (map (lambda (s) (and (not (memq s '(<> <...>))) (gensym)))
+ slots)))
+ `(let ,(delq! #f (map (lambda (t s) (and t (list t s))) temp slots))
+ (cut ,@(map (lambda (t s) (or t s)) temp slots)))))