First attempt at making pipe() work

Alas, this doesn't compile on OS X because of:

  moar(11870,0x7fff7bf29310) malloc: *** error for object 0x7fc8bbfaeae0: pointer being freed was not allocated

during stage parse.

src/core/IO.pm

@@ -462,3 +462,5 @@ sub MAKE-DIR-LIST(Str $abspath, Mu $test) {
     }
 }
 #?endif
+
+# vim: ft=perl6 expandtab sw=4

src/core/IO/Pipe.pm

@@ -1,5 +1,13 @@
 class IO::Pipe does IO does PIO {
-
+    has Str $.command;
+
+    method BUILD (:$command,Mu :$PIO,:$chomp,:$bin,:$encoding,:$nl) {
+        $!command = $command;
+        $!PIO := nqp::decont($PIO);
+        $!chomp = $chomp // True;
+        self.encoding($bin ?? 'binary' !! $encoding // 'utf8');
+        self.nl($nl // "\n");
+    }
 
 
 }

src/core/PIO.pm

@@ -1,6 +1,7 @@
 my role PIO {
     has $.PIO;
     has $.chomp;
+    has $.nl;
     has int $.ins;
 
     method close(PIO:D:) {
@@ -399,6 +400,12 @@ my role PIO {
     multi method encoding(PIO:D: $encoding) {
         nqp::setencoding($!PIO, NORMALIZE_ENCODING($encoding));
     }
+
+    proto method nl(|) { * }
+    multi method nl() { $!nl }
+    multi method nl($nl) {
+        nqp::setinputlinesep($!PIO, nqp::unbox_s($!nl = $nl));
+    }
 }
 
 # vim: ft=perl6 expandtab sw=4

src/core/io_operators.pm

@@ -138,14 +138,7 @@ multi sub open(
 }
 
 proto sub pipe(|) { * }
-multi sub pipe(
-  $path as Str,
-  :$bin,
-  :$enc   = 'utf8',
-  :$chomp = True,
-  :$nl    = "\n",
-  |c
-) {
+multi sub pipe( $command as Str, :$bin, :$enc, :$encoding, :$chomp, :$nl, |c) {
 
     my Mu $hash-with-containers := nqp::getattr(%*ENV, EnumMap, '$!storage');
     my Mu $hash-without := nqp::hash();
@@ -163,16 +156,14 @@ multi sub pipe(
 
     my str $errpath;   # what is this good for?
     # TODO: catch error, and fail()
-    my Mu $PIO := nqp::openpipe(
-      nqp::unbox_s($path),
+    my $PIO := nqp::openpipe(
+      nqp::unbox_s($command),
       nqp::unbox_s($*CWD.chop),
       $hash-without,
       $errpath,
     );
 
-    nqp::setencoding($PIO,NORMALIZE_ENCODING($enc)) if !$bin && $enc;
-    nqp::setinputlinesep($PIO,nqp::unbox_s($nl));
-    IO::Handle.new(:$path,:$PIO,:$chomp,:$nl,|c);
+    IO::Pipe.new(:$command,:$PIO,:$bin,:$encoding,:$chomp,:$nl,|c);
 }
 
 proto sub lines(|) { * }