+U_CAPI UBool U_EXPORT2
+uprv_isASCIILetter(char c) {
+#if U_CHARSET_FAMILY==U_EBCDIC_FAMILY
+ return
+ ('a'<=c && c<='i') || ('j'<=c && c<='r') || ('s'<=c && c<='z') ||
+ ('A'<=c && c<='I') || ('J'<=c && c<='R') || ('S'<=c && c<='Z');
+#else
+ return ('a'<=c && c<='z') || ('A'<=c && c<='Z');
+#endif
+}
+