From: David Kastrup <dak@gnu.org>
Date: Thu, 24 Nov 2011 15:13:01 +0000 (+0100)
Subject: Don't create closures for obvious constants in #{ ... #}
X-Git-Tag: release/2.15.21-1~44
X-Git-Url: https://git.donarmstrong.com/?a=commitdiff_plain;h=a06520dd711f070d1f6f69c6ea90bcb4bb19e2ab;p=lilypond.git

Don't create closures for obvious constants in #{ ... #}
---

diff --git a/scm/parser-ly-from-scheme.scm b/scm/parser-ly-from-scheme.scm
index f407a3dff0..7e1757123f 100644
--- a/scm/parser-ly-from-scheme.scm
+++ b/scm/parser-ly-from-scheme.scm
@@ -41,15 +41,20 @@ from @var{port} and return the corresponding Scheme music expression.
 			     (write-char c out)
 			     ;; a #scheme or $scheme expression
 			     (if (or (char=? c #\#) (char=? c #\$))
-				 (let ((p (ftell out)))
-				   (set! closures
-					 (cons (cons p (read copycat))
-					       closures))))))))))
+				 (let* ((p (ftell out))
+					(expr (read copycat)))
+				   ;; only put symbols and non-quote
+				   ;; lists into closures -- constants
+				   ;; don't need lexical environments
+				   ;; for evaluation.
+				   (if (or (symbol? expr)
+					   (and (pair? expr)
+						(not (eq? 'quote (car expr)))))
+				       (set! closures
+					     (cons `(cons ,p (lambda () ,expr))
+						   closures)))))))))))
     `(let* ((clone
-	     (ly:parser-clone parser (list ,@(map (lambda (c)
-						    `(cons ,(car c)
-							   (lambda () ,(cdr c))))
-						  (reverse! closures)))))
+	     (ly:parser-clone parser (list ,@closures)))
 	    (result (ly:parse-string-expression clone ,lily-string
 						,filename
 						,line)))