babel: perl: New variable assignment and expansion scheme

	* ob-perl.el (org-babel-execute:perl): Use generic expansion
	function
	(org-babel-expand-body:perl): Delete function
	(org-babel-variable-assignments:perl): New function

lisp/ob-perl.el

@@ -38,17 +38,6 @@
 (defvar org-babel-perl-command "perl"
   "Name of command to use for executing perl code.")
 
-(defun org-babel-expand-body:perl (body params)
-  "Expand BODY according to PARAMS, return the expanded body."
-  (let ((vars (mapcar #'cdr (org-babel-get-header params :var))))
-    (concat
-     (mapconcat ;; define any variables
-      (lambda (pair)
-        (format "$%s=%s;"
-                (car pair)
-                (org-babel-perl-var-to-perl (cdr pair))))
-      vars "\n") "\n" (org-babel-trim body) "\n")))
-
 (defun org-babel-execute:perl (body params)
   "Execute a block of Perl code with Babel.
 This function is called by `org-babel-execute-src-block'."
@@ -57,7 +46,8 @@ This function is called by `org-babel-execute-src-block'."
          (vars (nth 1 processed-params))
          (result-params (nth 2 processed-params))
          (result-type (nth 3 processed-params))
-         (full-body (org-babel-expand-body:perl body params))
+         (full-body (org-babel-expand-body:generic
+		     body params (org-babel-variable-assignments:perl params)))
 	(session (org-babel-perl-initiate-session session)))
     (org-babel-reassemble-table
      (org-babel-perl-evaluate session full-body result-type)
@@ -70,6 +60,15 @@ This function is called by `org-babel-execute-src-block'."
   "Prepare SESSION according to the header arguments in PARAMS."
   (error "Sessions are not supported for Perl."))
 
+(defun org-babel-variable-assignments:perl (params)
+  "Return list of perl statements assigning the block's variables"
+  (mapcar
+   (lambda (pair)
+     (format "$%s=%s;"
+	     (car pair)
+	     (org-babel-perl-var-to-perl (cdr pair))))
+   (mapcar #'cdr (org-babel-get-header params :var))))
+
 ;; helper functions
 
 (defun org-babel-perl-var-to-perl (var)