update benz (_ and ...)

extlib/benz

@@ -1 +1 @@
-Subproject commit 2d80522230358a4f3f2a1cd1af56da16d0f612d0
+Subproject commit c3acc4cb44bcf3baf9c50bb4667ad20c77660c3f

piclib/picrin/base.scm

@@ -8,13 +8,14 @@
           begin
           define-syntax)
 
+  (export syntax-error
+          let-syntax
+          letrec-syntax)
+
   (export let
           let*
           letrec
           letrec*
-          let-values
-          let*-values
-          define-values
           quasiquote
           unquote
           unquote-splicing
@@ -22,17 +23,16 @@
           or
           cond
           case
+          =>
+          else
           do
           when
           unless
-          let-syntax
-          letrec-syntax
-          include
-          =>
-          else
-          _
-          ...
-          syntax-error)
+          include)
+
+  (export let-values
+          let*-values
+          define-values)
 
   (export eq?
           eqv?

piclib/picrin/syntax-rules.scm

@@ -2,6 +2,16 @@
   (import (picrin base)
           (picrin macro))
 
+  (define-syntax define-auxiliary-syntax
+    (er-macro-transformer
+     (lambda (expr r c)
+       (list (r 'define-syntax) (cadr expr)
+             (list (r 'lambda) '_
+                   (list (r 'error) "invalid use of auxiliary syntax"))))))
+
+  (define-auxiliary-syntax _)
+  (define-auxiliary-syntax ...)
+
   (define (walk proc expr)
     (cond
      ((null? expr)
@@ -332,4 +342,6 @@
 
 	     `(,_syntax-error "malformed syntax-rules"))))))
 
-  (export syntax-rules))
+  (export syntax-rules
+          _
+          ...))

piclib/scheme/base.scm

@@ -4,8 +4,6 @@
           (picrin record)
           (picrin syntax-rules))
 
-  (export else => _ ...)
-
   ;; 4.1.2. Literal expressions
 
   (export quote)
@@ -30,6 +28,8 @@
 
   (export cond
           case
+          else
+          =>
           and
           or
           when
@@ -145,7 +145,9 @@
 
   ;; 4.3.2 Pattern language
 
-  (export syntax-rules)
+  (export syntax-rules
+          _
+          ...)
 
   ;; 4.3.3. Signaling errors in macro transformers