[nqp]: Add return statement.

src/NQP/Actions.pm

@@ -115,6 +115,10 @@ method statement_control:sym<for>($/) {
     make $past;
 }
 
+method statement_control:sym<return>($/) {
+    make PAST::Op.new( $<EXPR>.ast, :pasttype('return'), :node($/) );
+}
+
 ## Terms
 
 method noun:sym<variable>($/) { make $<variable>.ast; }
@@ -168,6 +172,7 @@ method routine_declarator:sym<sub>($/) { make $<routine_def>.ast; }
 method routine_def($/) {
     my $past := $<blockoid>.ast;
     $past.blocktype('declaration');
+    $past.control('return_pir');
     if $<deflongname> {
         my $name := ~$<deflongname>[0];
         $past.name($name);

src/NQP/Grammar.pm

@@ -89,6 +89,11 @@ token statement_control:sym<for> {
     <xblock>
 }
 
+token statement_control:sym<return> {
+    <sym> :s 
+    [ <EXPR> || <.panic: 'return requires an expression argument'> ]
+}
+
 ## Terms
 
 token noun:sym<variable>           { <variable> }

t/nqp/20-return.t

@@ -0,0 +1,23 @@
+#! nqp
+
+# implicit and explicit returns from subs
+
+plan(3);
+
+sub foo() { 1; }
+
+
+sub bar() {
+    return 2;
+    0;
+}
+
+sub baz() {
+    if (1) { return 3; }
+    0;
+}
+
+ok( foo() == 1 , 'last value in block' );
+ok( bar() == 2 , 'explicit return value in block');
+ok( baz() == 3 , 'explicit return from nested block');
+