Prevent $*OUT lookup for each eigenstate with put / print

Although one probably shouldn't print or put a Junction, having a
dynamic variable lookup for each eigenstate can be pretty expensive.
Also, convert to calling .print immediately, for better interface
with custom classes acting like $*OUT.

src/core.c/IO/Handle.pm6

@@ -655,7 +655,9 @@ my class IO::Handle {
         self.print(sprintf |c);
     }
 
-    multi method print(Junction:D \j) { j.THREAD: { self.print: $_ } }
+    multi method print(IO::Handle:D: Junction:D \j) {
+        j.THREAD: { self.print: $_ }
+    }
     multi method print(IO::Handle:D: Str:D \x --> True) {
         $!decoder
           ?? self.WRITE($!encoder.encode-chars(x))
@@ -678,7 +680,9 @@ my class IO::Handle {
         }
     }
 
-    multi method put(Junction:D \j) { j.THREAD: { self.put: $_ } }
+    multi method put(IO::Handle:D: Junction:D \j) {
+        j.THREAD: { self.print: nqp::concat(.Str,$!nl-out) }
+    }
     multi method put(IO::Handle:D: --> True) {
         $!decoder
           ?? self.WRITE($!encoder.encode-chars($!nl-out))

src/core.c/io_operators.pm6

@@ -2,7 +2,10 @@ my class IO::ArgFiles { ... }
 
 proto sub print(|) {*}
 multi sub print(--> True) { }    # nothing to do
-multi sub print(Junction:D \j) { j.THREAD(&print) }
+multi sub print(Junction:D \j) {
+    my $out := $*OUT;
+    j.THREAD: { $out.print: .Str }
+}
 multi sub print(Str:D \x) { $*OUT.print(x) }
 multi sub print(\x) { $*OUT.print(x.Str) }
 multi sub print(|) {
@@ -35,7 +38,8 @@ multi sub put() {
     .print: .nl-out
 }
 multi sub put(Junction:D \j) {
-    j.THREAD(&put)
+    my $out := $*OUT;
+    j.THREAD: { $out.print: nqp::concat(.Str,$out.nl-out) }
 }
 multi sub put(\x) {
     $_ := $*OUT;