# HG changeset patch
# User Aidan Kehoe <kehoea@parhasard.net>
# Date 1281875350 -3600
# Node ID 808131ba4a5737d4eb0ecee301c98cba84dab91c
# Parent  f3eca926258e6ae9d6a7af522c576d80a377ac2c
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.

diff -r f3eca926258e -r 808131ba4a57 src/ChangeLog
--- a/src/ChangeLog	Sat Jul 24 17:38:35 2010 +0100
+++ b/src/ChangeLog	Sun Aug 15 13:29:10 2010 +0100
@@ -1,3 +1,15 @@
+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.
+
 2010-07-24  Aidan Kehoe  <kehoea@parhasard.net>
 
 	* lisp.h (PARSE_KEYWORDS):
diff -r f3eca926258e -r 808131ba4a57 src/lisp.h
--- a/src/lisp.h	Sat Jul 24 17:38:35 2010 +0100
+++ b/src/lisp.h	Sun Aug 15 13:29:10 2010 +0100
@@ -5355,9 +5355,7 @@
 int locate_file (Lisp_Object, Lisp_Object, Lisp_Object, Lisp_Object *, int);
 EXFUN (Flocate_file_clear_hashing, 1);
 int isfloat_string (const char *);
-#ifdef HAVE_RATIO
 int isratio_string (const char *);
-#endif
 
 /* Well, I've decided to enable this. -- ben */
 /* And I've decided to make it work right.  -- sb */
diff -r f3eca926258e -r 808131ba4a57 src/lread.c
--- a/src/lread.c	Sat Jul 24 17:38:35 2010 +0100
+++ b/src/lread.c	Sun Aug 15 13:29:10 2010 +0100
@@ -2876,7 +2876,6 @@
 	      || state == (DOT_CHAR|TRAIL_INT|E_CHAR|EXP_INT)));
 }
 
-#ifdef HAVE_RATIO
 int
 isratio_string (const char *cp)
 {
@@ -2907,7 +2906,7 @@
   return *cp == '\0' || *cp == ' ' || *cp =='\t' || *cp == '\n' ||
     *cp == '\r' || *cp == '\f';
 }
-#endif
+
 
 static void *
 sequence_reader (Lisp_Object readcharfun,
diff -r f3eca926258e -r 808131ba4a57 src/print.c
--- a/src/print.c	Sat Jul 24 17:38:35 2010 +0100
+++ b/src/print.c	Sun Aug 15 13:29:10 2010 +0100
@@ -2027,7 +2027,7 @@
 
     for (; confusing < size; confusing++)
       {
-        if (!isdigit (data[confusing]))
+	if (!isdigit (data[confusing]) && '/' != data[confusing])
           {
             confusing = 0;
             break;
@@ -2039,7 +2039,8 @@
       /* #### Ugh, this is needlessly complex and slow for what we
          need here.  It might be a good idea to copy equivalent code
          from FSF.  --hniksic */
-      confusing = isfloat_string ((char *) data);
+      confusing = isfloat_string ((char *) data)
+	|| isratio_string ((char *) data);
     if (confusing)
       write_ascstring (printcharfun, "\\");
   }
diff -r f3eca926258e -r 808131ba4a57 tests/ChangeLog
--- a/tests/ChangeLog	Sat Jul 24 17:38:35 2010 +0100
+++ b/tests/ChangeLog	Sun Aug 15 13:29:10 2010 +0100
@@ -1,3 +1,9 @@
+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.
+
 2010-07-24  Aidan Kehoe  <kehoea@parhasard.net>
 
 	* automated/lisp-tests.el:
diff -r f3eca926258e -r 808131ba4a57 tests/automated/lisp-tests.el
--- 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