Print symbols with ratio-like names and the associated ratios distinctly. src/ChangeLog addition: 2010-08-15 Aidan Kehoe <kehoea@parhasard.net> * print.c (print_symbol): Escape any symbols that look like ratios, in the same way we do symbols that look like floats or integers. Prevents confusion in the Lisp reader. * lread.c (isratio_string): Make this available even on builds without HAVE_RATIO, so we can print symbols that look like ratios with the appropriate escapes. * lisp.h: Make isratio_string available even if HAVE_RATIO is not defined. tests/ChangeLog addition: 2010-08-15 Aidan Kehoe <kehoea@parhasard.net> * automated/lisp-tests.el: Test that symbols with names that look like ratios are printed distinctly from the equivalent ratios.

--- a/tests/automated/lisp-tests.el	Sat Jul 24 17:38:35 2010 +0100
+++ b/tests/automated/lisp-tests.el	Sun Aug 15 13:29:10 2010 +0100
@@ -2374,4 +2374,10 @@
 				     (garbage-collect))))))
  "checking we can amputate lists without crashing #'reduce")
 
+(when (featurep 'ratio)
+  (Assert (not (eql '1/2 (read (prin1-to-string (intern "1/2")))))
+	  "checking symbols with ratio-like names are printed distinctly")
+  (Assert (not (eql '1/5 (read (prin1-to-string (intern "2/10")))))
+	  "checking symbol named \"2/10\" not eql to ratio 1/5 on read"))
+
 ;;; end of lisp-tests.el