1 files changed, 16 insertions, 15 deletions
diff --git a/rprt-engine/src/selection_functions/mod.rs b/rprt-engine/src/selection_functions/mod.rs
index b753200..85c333e 100644
--- a/rprt-engine/src/selection_functions/mod.rs
+++ b/rprt-engine/src/selection_functions/mod.rs
@@ -3,9 +3,9 @@ use crate::{
     selection::Selection,
     selection_functions::{
         function_character::selection_function_character,
+        function_empty::selection_function_empty,
         function_end::selection_function_end,
         result_transformation::{complement_transform, conditional_transform},
-        types::SFArguments,
     },
     state::EditorState,
 };
@@ -16,7 +16,9 @@ mod function_end;
 mod result_transformation;
 mod types;
 
-pub use crate::selection_functions::types::{SFError, SFResult};
+pub use crate::selection_functions::types::{
+    SelectionFunction, SelectionFunctionError, UnparameterisedSelectionFunction,
+};
 
 pub fn evaluate_selection_function(
     es: &EditorState,
@@ -25,31 +27,30 @@ pub fn evaluate_selection_function(
     result_transform: Option<ResultTransform>,
     left: Option<Selection>,
     right: Option<Selection>,
-) -> SFResult {
-    let sf_args = match (left, right) {
-        (None, None) => Ok(SFArguments::Niladic { es }),
-        (Some(left), None) => Ok(SFArguments::Monadic { es, left }),
-        (Some(left), Some(right)) => Ok(SFArguments::Dyadic { es, left, right }),
-        _ => Err(SFError::NoLeftArgument),
-    }?;
+) -> Result<Selection, SelectionFunctionError> {
     let res = match sf {
         BuiltinSelectionFn::CharOffset(off) => {
-            selection_function_character(off, &sf_args, search_mod)
+            selection_function_character(off, es, left.as_ref(), right.as_ref(), search_mod)
+        }
+        BuiltinSelectionFn::Empty => {
+            selection_function_empty(es, left.as_ref(), right.as_ref(), search_mod)
+        }
+        BuiltinSelectionFn::EndOfBuffer => {
+            selection_function_end(es, left.as_ref(), right.as_ref(), search_mod)
         }
-        BuiltinSelectionFn::EndOfBuffer => selection_function_end((), &sf_args, search_mod),
-        x => Err(SFError::NotImplemented(x).into()),
+        x => Err(SelectionFunctionError::NotImplemented(x)),
     }?;
 
     if let Some(result_transform) = result_transform {
         match result_transform {
             ResultTransform::Complement => complement_transform(es, res),
-            ResultTransform::Conditional => conditional_transform(res, &sf_args),
+            ResultTransform::Conditional => conditional_transform(res, left.as_ref()),
             ResultTransform::ConditionalComplement => {
                 let res = complement_transform(es, res)?;
-                conditional_transform(res, &sf_args)
+                conditional_transform(res, left.as_ref())
             }
             ResultTransform::ComplementConditional => {
-                let res = conditional_transform(res, &sf_args)?;
+                let res = conditional_transform(res, left.as_ref())?;
                 complement_transform(es, res)
             }
         }