gistfile1.none

diff --git a/src/Perl6/Metamodel/BOOTSTRAP.pm b/src/Perl6/Metamodel/BOOTSTRAP.pm
index 9d5958c..d30cc85 100644
--- a/src/Perl6/Metamodel/BOOTSTRAP.pm
+++ b/src/Perl6/Metamodel/BOOTSTRAP.pm
@@ -363,6 +363,7 @@ my stub Scalar metaclass Perl6::Metamodel::ClassHOW { ... };
 Scalar.HOW.add_parent(Scalar, Any);
 Scalar.HOW.add_attribute(Scalar, BOOTSTRAPATTR.new(:name<$!descriptor>, :type(Mu)));
 Scalar.HOW.add_attribute(Scalar, BOOTSTRAPATTR.new(:name<$!value>, :type(Mu)));
+Scalar.HOW.add_attribute(Scalar, BOOTSTRAPATTR.new(:name<$!whence>, :type(Mu)));
 pir::set_scalar_container_type__vP(Scalar);
 
 # Scalar needs to be registered as a container type.
diff --git a/src/binder/container.c b/src/binder/container.c
index dc968c7..ed63e7f 100644
--- a/src/binder/container.c
+++ b/src/binder/container.c
@@ -64,6 +64,12 @@ void Rakudo_cont_store(PARROT_INTERP, PMC *cont, PMC *value,
                     "Type check failed in assignment");
             }
         }
+
+        if (!PMC_IS_NULL(scalar->whence)) {
+            PMC *cappy = Parrot_pmc_new(interp, enum_class_CallContext);
+            Parrot_pcc_invoke_from_sig_object(interp, scalar->whence, cappy);
+            scalar->whence = PMCNULL;
+        }
         
         /* If we get here, all is fine; store the value. */
         scalar->value = value;
diff --git a/src/binder/container.h b/src/binder/container.h
index bdf92ae..081982b 100644
--- a/src/binder/container.h
+++ b/src/binder/container.h
@@ -15,6 +15,7 @@ typedef struct {
     PMC    *spill;              /* Attribute spill storage. */
     PMC    *descriptor;         /* Container descriptor. */
     PMC    *value;              /* The currently held value. */
+    PMC    *whence;             /* Any whence property */
 } Rakudo_Scalar;
 
 /* Various functions related to container manipulations. */