coercion methods to FatRat

src/core/Int.pm

@@ -30,6 +30,9 @@ my class Int {
     method Rat(Int:D: $?) {
         Rat.new(self, 1);
     }
+    method FatRat(Int:D: $?) {
+        FatRat.new(self, 1);
+    }
 
     method abs(Int:D:) {
         nqp::abs_I(self, Int)

src/core/Num.pm

@@ -30,7 +30,7 @@ my class Num {
         }
     }
 
-    method Rat(Num:D: Real $epsilon = 1.0e-6) {
+    method Rat(Num:D: Real $epsilon = 1.0e-6, :$fat) {
         my sub modf($num) { my $q = $num.Int; $num - $q, $q; }
 
         (self == $Inf || self == -$Inf) && fail("Cannot coerce Inf to a Rat");
@@ -57,8 +57,10 @@ my class Num {
         # smaller denominator but it is not (necessarily) the Rational
         # with the smallest denominator that has less than $epsilon error.
         # However, to find that Rational would take more processing.
-
-        ($signum * $b) / $d;
+        $fat ?? FatRat.new($signum * $b, $d) !! ($signum * $b) / $d;
+    }
+    method FatRat(Num:D: Real $epsilon = 1.0e-6) {
+        self.Rat($epsilon, :fat);
     }
 
     multi method atan2(Num:D: Num:D $x = 1e0) {

src/core/Rat.pm

@@ -55,7 +55,6 @@ my role Rational is Real {
     }
 }
 
-my class FatRat { ... }
 # XXX: should also be Cool
 my class Rat    does Rational { 
     method Rat   (Rat:D: Real $?) { self }

src/core/stubs.pm

@@ -10,6 +10,7 @@ my class KeyHash is Iterable does Associative { }
 my class Seq is List does Positional { }
 my class Exception { ... }
 my class X::AdHoc  { ... }
+my class FatRat    { ... }
 
 sub DYNAMIC(\$name) is rw { 
     my Mu $x := pir::find_dynamic_lex__Ps(nqp::unbox_s($name));