Hi,
I have attached the below patch in an attempt to fix this. I notice that printing.el requires lpr.el, and pr-switches function anyways uses lpr-flatten-list from lpr.el. So there should be no harm using lpr-eval-switch instead of ps-eval-switch. I have verified that lpr-eval-switch is the exact same function as the now obsolete ps-eval-switch; just different names.
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From 4af9c6403b5917aca27490cc331a36dd6e1222c3 Mon Sep 17 00:00:00 2001
Date: Wed, 11 May 2016 12:45:42 -0400
Subject: [PATCH] Fix reference to obsolete fn ps-eval-switch
The `lpr-eval-switch' is functionally the same as `ps-eval-switch' which
was obsoleted in 2cdeb903c57126d3ad5f0cbd72e182584b76ee29. So using
that instead (Bug#19717).
* printing.el (pr-switches): Use lpr-eval-switch instead of ps-eval-switch.
---
lisp/printing.el | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lisp/printing.el b/lisp/printing.el
index 3bd5a67..a336aeb 100644
--- a/lisp/printing.el
+++ b/lisp/printing.el
@@ -5673,7 +5673,7 @@ pr-switches
(or (listp switches)
(error "%S should have a list of strings" mess))
(lpr-flatten-list ; dynamic evaluation
- (mapcar 'ps-eval-switch switches)))
+ (mapcar 'lpr-eval-switch switches)))
(defun pr-ps-preview (kind n-up filename mess)
--
2.6.0.rc0.24.gec371ff