Index: unicodeobject.c
===================================================================
RCS file: /cvsroot/python/python/dist/src/Objects/unicodeobject.c,v
retrieving revision 2.86
diff -u -r2.86 unicodeobject.c
--- unicodeobject.c	2001/04/21 02:46:11	2.86
+++ unicodeobject.c	2001/04/21 12:11:15
@@ -90,6 +90,8 @@
 static PyUnicodeObject *unicode_freelist;
 static int unicode_freelist_size;
 
+static PyUnicodeObject *unicode_ascii[128];
+
 /* Default encoding to use and assume when NULL is passed as encoding
    parameter; it is initialized by _PyUnicode_Init().
 
@@ -1652,6 +1654,19 @@
 {
     PyUnicodeObject *v;
     Py_UNICODE *p;
+
+    if (size == 1 && *(unsigned char*)s < 128) {
+	    v = unicode_ascii[(int)*s];
+	    if (!v) {
+		    v = _PyUnicode_New(1);
+		    if (!v)
+			    return NULL;
+		    v->str[0] = *s;
+		    unicode_ascii[(int)*s] = v;
+	    }
+	    Py_INCREF(v);
+	    return (PyObject*)v;
+    }
     
     /* ASCII is equivalent to the first 128 ordinals in Unicode. */
     v = _PyUnicode_New(size);
@@ -5184,6 +5199,8 @@
 
 void _PyUnicode_Init(void)
 {
+    int i;
+
     /* Doublecheck the configuration... */
     if (sizeof(Py_UNICODE) != 2)
         Py_FatalError("Unicode configuration error: "
@@ -5194,6 +5211,9 @@
     unicode_freelist_size = 0;
     unicode_empty = _PyUnicode_New(0);
     strcpy(unicode_default_encoding, "ascii");
+
+    for (i = 0; i < 128; i++)
+	unicode_ascii[i] = NULL;
 }
 
 /* Finalize the Unicode implementation */
@@ -5202,9 +5222,17 @@
 _PyUnicode_Fini(void)
 {
     PyUnicodeObject *u;
+    int i;
 
     Py_XDECREF(unicode_empty);
     unicode_empty = NULL;
+
+    for (i = 0; i < 128; i++) {
+	if (unicode_ascii[i]) {
+	    Py_DECREF(unicode_ascii[i]);
+	    unicode_ascii[i] = NULL;
+	}
+    }
 
     for (u = unicode_freelist; u != NULL;) {
 	PyUnicodeObject *v = u;