Arch: rebar, make it possible to create a rebar without existence of a Structure

src/Mod/Arch/ArchRebar.py

@@ -76,6 +76,12 @@ def makeRebar(baseobj=None,sketch=None,diameter=None,amount=1,offset=None,name="
         if FreeCAD.GuiUp:
             sketch.ViewObject.hide()
         obj.Host = baseobj
+    elif sketch and not baseobj:
+        # a rebar could be based on a wire without the existance of a Structure
+        obj.Base = sketch
+        if FreeCAD.GuiUp:
+            sketch.ViewObject.hide()
+        obj.Host = None
     if diameter:
         obj.Diameter = diameter
     else: