* *.h: Use SCM_NIMP(X) && in all the FOOP macros.

[bpt/guile.git] / libguile / strings.h

diff --git a/libguile/strings.h b/libguile/strings.h
index 5f5334e..279dd57 100644 (file)
--- a/libguile/strings.h
+++ b/libguile/strings.h
@@ -42,6 +42,9 @@
  * If you write modifications of your own for GUILE, it is your choice
  * whether to permit this exception to apply to your modifications.
  * If you do not wish that, delete this exception notice.  */
+
+/* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
+   gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
 \f
 
 #include "libguile/__scm.h"
@@ -52,11 +55,11 @@
 
 \f
 
-#define SCM_STRINGP(x) (SCM_TYP7S(x)==scm_tc7_string)
+#define SCM_STRINGP(x) (SCM_NIMP(x) && (SCM_TYP7S(x)==scm_tc7_string))
 #define SCM_NSTRINGP(x) (!SCM_STRINGP(x))
 
 /* Is X a writable string (i.e., not a substring)?  */
-#define SCM_RWSTRINGP(x) (SCM_TYP7(x) == scm_tc7_string)
+#define SCM_RWSTRINGP(x) (SCM_NIMP(x) && (SCM_TYP7(x) == scm_tc7_string))
 #define SCM_NRWSTRINGP(x) (! SCM_RWSTRINGP (x))
 
 \f