cleanup and break out functions

Signed-off-by: Ava Hahn <ava@aidanis.online>

the_rewrite/src/func.rs

@@ -74,7 +74,7 @@ pub struct ExternalOperation<'a> {
  * or a syntax tree to eval with the arguments
  */
 pub enum Operation<'a> {
-    Internal(Box<dyn for<'b> Fn(&'b Seg, &'b mut VTable, &'b mut FTable) -> Ctr<'b>>),
+    Internal(Box<dyn Fn(&'a Seg, &'a mut VTable, &'a mut FTable) -> Ctr<'a>>),
     External(ExternalOperation<'a>),
 }
 
@@ -88,7 +88,6 @@ pub enum Args {
     Strict(Vec<Type>),
 }
 
-// function which does not need args checked
 pub struct Function<'a> {
     pub function: Operation<'a>,
     pub name: String,