Document Rational.base-repeating

lib/Type/Rational.pod

@@ -45,4 +45,25 @@ Returns a list of the numerator and denominator.
 Returns a normalized Rational object, i.e. with positive denominator, and
 numerator and denominator coprime.
 
+=head2 method base-repeating
+
+    method base-repeating(Rational:D: Int:D() $base)
+
+Returns a list of two strings that, when concatenated, represent the number in
+base C<$base>. The second element is the one that repeats. For example:
+
+    my ($non-rep, $repeating) = (19/3).base-repeating(10);
+    say $non-rep;                               # 6.
+    say $rep;                                   # 3
+    printf '%s(%s)', $non-rep, $repeating;      # 6.(3)
+
+19/3 is 6.333333... with the 3 repeating indefinitely.
+
+If no repetition occurs, the second string is empty:
+
+    say (5/2).base-repeating(10).perl;          # ("2.5", "")
+
+The precision for detrmining the repeating group is limited to 1000
+characters, above that, the second string is C<???>.
+
 =end pod