Cast function to the appropriate signal otherwise it won't match the

expected runtime type.

This is a limitation of signals using Go's runtime type conversion.

funcs.go

@@ -23,17 +23,19 @@ func DependencyMapper() *mappers.DependencyMapper {
 // AttachTemplateVar attaches a variable to the global template context with the
 // specified name and value.
 func AttachTemplateVar(name string, val interface{}) {
-	signals.Connect(SigEachRoute, func(r *Router, rt *Route) {
-		rt.Renderer.GlobalContext(name, val)
-	})
+	signals.Connect(SigEachRoute,
+		OnEachRoute(func(r *Router, rt *Route) {
+			rt.Renderer.GlobalContext(name, val)
+		}))
 }
 
 // AttachTemplateFunc attaches a function or callable to the global template
 // context using the provided name.
 func AttachTemplateFunc(name string, fn interface{}) {
-	signals.Connect(SigEachRoute, func(r *Router, rt *Route) {
-		rt.Renderer.SetFunc(name, fn)
-	})
+	signals.Connect(SigEachRoute,
+		OnEachRoute(func(r *Router, rt *Route) {
+			rt.Renderer.SetFunc(name, fn)
+		}))
 }
 
 // Private method for binding individual routers to the backend Chi muxer.