Index: numeric.c
===================================================================
--- numeric.c	(revision 27054)
+++ numeric.c	(working copy)
@@ -547,16 +547,16 @@
 
 /*
  *  call-seq:
- *     flt.to_s  ->  string
+ *     flt.inspect  ->  string
  *
- *  Returns a string containing a representation of self. As well as a
+ *  Returns a string containing a full representation of self. As well as a
  *  fixed or exponential form of the number, the call may return
  *  ``<code>NaN</code>'', ``<code>Infinity</code>'', and
  *  ``<code>-Infinity</code>''.
  */
 
 static VALUE
-flo_to_s(VALUE flt)
+flo_inspect(VALUE flt)
 {
     enum {decimal_mant = DBL_MANT_DIG-DBL_DIG};
     enum {float_dig = DBL_DIG+1};
@@ -590,6 +590,46 @@
 }
 
 /*
+ *  call-seq:
+ *     flt.to_s    => string
+ *
+ *  Returns a string containing a human readable representation of self. As well as a
+ *  fixed or exponential form of the number, the call may return
+ *  ``<code>NaN</code>'', ``<code>Infinity</code>'', and
+ *  ``<code>-Infinity</code>''.
+ */
+
+static VALUE
+flo_to_s(VALUE flt)
+{
+    char buf[32];
+    double value = RFLOAT_VALUE(flt);
+    char *p, *e;
+
+    if (isinf(value))
+	return rb_usascii_str_new2(value < 0 ? "-Infinity" : "Infinity");
+    else if(isnan(value))
+	return rb_usascii_str_new2("NaN");
+
+    snprintf(buf, sizeof(buf), "%#.15g", value); /* ensure to print decimal point */
+    if (!(e = strchr(buf, 'e'))) {
+	e = buf + strlen(buf);
+    }
+    if (!ISDIGIT(e[-1])) { /* reformat if ended with decimal point (ex 111111111111111.) */
+	snprintf(buf, sizeof(buf), "%#.14e", value);
+	if (!(e = strchr(buf, 'e'))) {
+	    e = buf + strlen(buf);
+	}
+    }
+    p = e;
+    while (p[-1]=='0' && ISDIGIT(p[-2]))
+	p--;
+    memmove(p, e, strlen(e)+1);
+    return rb_usascii_str_new2(buf);
+}
+
+
+/*
  * MISSING: documentation
  */
 
@@ -3339,6 +3379,7 @@
     rb_define_const(rb_cFloat, "NAN", DBL2NUM(NAN));
 
     rb_define_method(rb_cFloat, "to_s", flo_to_s, 0);
+    rb_define_method(rb_cFloat, "inspect", flo_inspect, 0);
     rb_define_method(rb_cFloat, "coerce", flo_coerce, 1);
     rb_define_method(rb_cFloat, "-@", flo_uminus, 0);
     rb_define_method(rb_cFloat, "+", flo_plus, 1);