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+;;; Tree-il canonicalizer
+
+;; Copyright (C) 2011, 2012, 2013 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 3 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
+
+;;; Code:
+
+(define-module (language tree-il canonicalize)
+ #:use-module (language tree-il)
+ #:use-module (ice-9 match)
+ #:use-module (srfi srfi-1)
+ #:export (canonicalize))
+
+(define (tree-il-any proc exp)
+ (tree-il-fold (lambda (exp res)
+ (or res (proc exp)))
+ (lambda (exp res) res)
+ #f exp))
+
+(define (canonicalize x)
+ (post-order
+ (lambda (x)
+ (match x
+ (($ <let> src () () () body)
+ body)
+ (($ <letrec> src _ () () () body)
+ body)
+ (($ <fix> src () () () body)
+ body)
+ (($ <lambda> src meta #f)
+ ;; Give a body to case-lambda with no clauses.
+ (make-lambda
+ src meta
+ (make-lambda-case
+ #f '() #f #f #f '() '()
+ (make-primcall
+ #f
+ 'throw
+ (list (make-const #f 'wrong-number-of-args)
+ (make-const #f #f)
+ (make-const #f "Wrong number of arguments")
+ (make-const #f '())
+ (make-const #f #f)))
+ #f)))
+ (($ <prompt> src escape-only? tag body handler)
+ ;; The prompt handler should be a simple lambda, so that we
+ ;; can inline it.
+ (match handler
+ (($ <lambda> _ _
+ ($ <lambda-case> _ req #f rest #f () syms body #f))
+ x)
+ (else
+ (let ((handler-sym (gensym))
+ (args-sym (gensym)))
+ (make-let
+ #f (list 'handler) (list handler-sym) (list handler)
+ (make-prompt
+ src escape-only? tag body
+ (make-lambda
+ #f '()
+ (make-lambda-case
+ #f '() #f 'args #f '() (list args-sym)
+ (make-primcall
+ #f 'apply
+ (list (make-lexical-ref #f 'handler handler-sym)
+ (make-lexical-ref #f 'args args-sym)))
+ #f))))))))
+ (_ x)))
+ x))