Make $x<does><not><exist> not explode.

jnthn · Apr 14, 2013 · 9ceb63a · 9ceb63a
1 parent b7c3945
commit 9ceb63a
Showing 1 changed file with 32 additions and 4 deletions.
diff --git a/lib/QAST/JASTCompiler.nqp b/lib/QAST/JASTCompiler.nqp
@@ -3008,11 +3008,15 @@ class QAST::CompilerJAST {
     }
 
     multi method as_jast(QAST::VarWithFallback $node, :$want) {
-        my $var_res := self.compile_var($node);
-        if $*BINDVAL || $var_res.type != $RT_OBJ {
-            $var_res
+        if $*BINDVAL {
+            self.compile_var($node)
         }
-        else {
+        elsif $node.scope ne 'positional' && $node.scope ne 'associative' {
+            my $var_res := self.compile_var($node);
+            if ($var_res.type != $RT_OBJ) {
+                return $var_res;
+            }
+
             my $il := JAST::InstructionList.new();
             $il.append($var_res.jast);
             $*STACK.obtain($il, $var_res);
@@ -3029,6 +3033,30 @@ class QAST::CompilerJAST {
 
             result($il, $RT_OBJ);
         }
+        else {
+            my $fb_temp := $node.unique('fb_tmp');
+            self.as_jast(QAST::Op.new(
+                :op('ifnull'),
+                QAST::Op.new(
+                    :op('if'),
+                    QAST::Op.new(
+                        :op('isconcrete'),
+                        QAST::Op.new(
+                            :op('bind'),
+                            QAST::Var.new( :name($fb_temp), :scope('local'), :decl('var') ),
+                            $node[0]
+                        )
+                    ),
+                    QAST::Var.new(
+                        :scope($node.scope),
+                        QAST::Var.new( :name($fb_temp), :scope('local') ),
+                        $node[1]
+                    ),
+                    QAST::Op.new( :op('null') )
+                 ),
+                $node.fallback
+            ))
+        }
     }
 
     method compile_var($node) {