diff --git a/src/bin.rs b/src/bin.rs
index 8401cbd..5c36944 100644
--- a/src/bin.rs
+++ b/src/bin.rs
@@ -5,6 +5,7 @@ use parser::Filter;
 use parser::OwnedLiteral;
 use parser::Template;
 use renderer::compile_template;
+use renderer::Castable;
 use renderer::CompileError;
 use renderer::ContextElement;
 use renderer::DustRenderer;
@@ -312,6 +313,12 @@ impl Loopable for serde_json::Value {
     }
 }
 
+impl Castable for serde_json::Value {
+    fn cast_to_type<'a>(&'a self, target: &str) -> Option<IceResult<'a>> {
+        todo!()
+    }
+}
+
 impl CompareContextElement for serde_json::Value {
     fn equals(&self, other: &dyn ContextElement) -> bool {
         // Handle other serde_json::Value
diff --git a/src/renderer/context_element.rs b/src/renderer/context_element.rs
index 5ef6e3c..7edd71d 100644
--- a/src/renderer/context_element.rs
+++ b/src/renderer/context_element.rs
@@ -17,6 +17,7 @@ pub trait ContextElement:
     + CompareContextElement
     + FromContextElement
     + IntoRcIce
+    + Castable
 {
 }
 
@@ -54,6 +55,10 @@ pub trait Loopable {
     fn get_loop_elements(&self) -> Vec<&dyn ContextElement>;
 }
 
+pub trait Castable {
+    fn cast_to_type<'a>(&'a self, target: &str) -> Option<IceResult<'a>>;
+}
+
 pub trait CastToAny {
     fn to_any(&self) -> &dyn Any;
 }
diff --git a/src/renderer/mod.rs b/src/renderer/mod.rs
index cf5ec08..571a02b 100644
--- a/src/renderer/mod.rs
+++ b/src/renderer/mod.rs
@@ -11,6 +11,7 @@ mod renderer;
 mod select_context;
 mod walking;
 
+pub use context_element::Castable;
 pub use context_element::CompareContextElement;
 pub use context_element::ContextElement;
 pub use context_element::IceResult;
diff --git a/src/renderer/parameters_context.rs b/src/renderer/parameters_context.rs
index 23b720d..026cf68 100644
--- a/src/renderer/parameters_context.rs
+++ b/src/renderer/parameters_context.rs
@@ -9,6 +9,7 @@ use crate::renderer::context_element::IceResult;
 use crate::renderer::context_element::IntoContextElement;
 use crate::renderer::math::MathNumber;
 use crate::renderer::walking::walk_path;
+use crate::renderer::Castable;
 use crate::renderer::DustRenderer;
 use crate::renderer::Loopable;
 use crate::renderer::RenderError;
@@ -167,6 +168,12 @@ impl Walkable for OwnedLiteral {
     }
 }
 
+impl Castable for OwnedLiteral {
+    fn cast_to_type<'a>(&'a self, target: &str) -> Option<IceResult<'a>> {
+        todo!()
+    }
+}
+
 impl CompareContextElement for OwnedLiteral {
     fn equals(&self, other: &dyn ContextElement) -> bool {
         // If its an OwnedLiteral then compare them directly,
diff --git a/src/renderer/renderer.rs b/src/renderer/renderer.rs
index aae1fd0..e282791 100644
--- a/src/renderer/renderer.rs
+++ b/src/renderer/renderer.rs
@@ -964,6 +964,13 @@ impl<'a> DustRenderer<'a> {
                 .map(|ice| ice.get_context_element_reference())
         });
 
+        // TODO convert string to number or render NaN
+
+        println!(
+            "Doing {:?} {:?} {:?}",
+            left_side, method_rendered, right_side
+        );
+
         return match method_rendered.as_str() {
             "add" => match (left_side_ce, right_side_ce) {
                 (None, _) | (Some(Err(_)), _) | (_, None) | (_, Some(Err(_))) => None,