Some basic train and parenthesis parsing, things are beginning to become exciting

1 files changed, 29 insertions, 43 deletions

diff --git a/rprt-engine/src/expression.rs b/rprt-engine/src/expression.rs
index 68849cb..1ee898e 100644
--- a/rprt-engine/src/expression.rs
+++ b/rprt-engine/src/expression.rs
@@ -1,55 +1,32 @@
 #[derive(Debug, Clone, PartialEq)]
-pub enum SelectionValuedExpr {
-    // Nullary selection function application
-    NullaryApplicationS(SelectionFn),
-    NullaryApplicationT(TextFn),
-
-    // Monadic selection function application: α F
-    MonadicApplicationS {
-        arg: Box<SelectionValuedExpr>,
-        func: SelectionFn,
-    },
-    // Monadic selection function application: F τ
-    MonadicApplicationT {
-        arg: Box<TextValuedExpr>,
-        func: TextFn,
-    },
-
-    // Dyadic selection function application: α F β
-    DyadicApplicationS {
-        left: Box<SelectionValuedExpr>,
-        right: Box<SelectionValuedExpr>,
-        func: SelectionFn,
-    },
-    // Dyadic text function application: α F τ
-    DyadicApplicationT {
-        left: Box<SelectionValuedExpr>,
-        right: Box<SelectionValuedExpr>,
-        func: SelectionFn,
-    },
-}
-
-#[derive(Debug, Clone, PartialEq)]
-pub enum TextValuedExpr {
-    // Selection coerced to text (implicit coercion)
-    FromSelection(Box<SelectionValuedExpr>),
-}
-
-#[derive(Debug, Clone, PartialEq)]
-pub enum SelectionFn {
-    Function {
+pub enum Composite {
+    SelectionFunction {
         func: BuiltinSelectionFn,
         search_mod: Option<SearchModifier>,
         result_transform: Option<ResultTransform>,
     },
 
+    TextFunction {
+        func: BuiltinTextFn,
+        swapped: bool,
+    },
+
     Hook {
         kind: HookKind,
-        left: Box<SelectionFn>,
-        right: Box<SelectionFn>,
+        left: Box<Composite>,
+        right: Box<Composite>,
     },
 
-    Train(Vec<SelectionFn>),
+    Train2 {
+        f: Box<Composite>,
+        g: Box<Composite>,
+    },
+
+    Train3 {
+        f: Box<Composite>,
+        g: Box<Composite>,
+        h: Box<Composite>,
+    },
 }
 
 #[derive(Debug, Clone, PartialEq)]
@@ -65,7 +42,16 @@ pub enum TextFn {
         right: Box<TextFn>,
     },
 
-    Train(Vec<TextFn>),
+    Train2 {
+        f: Box<TextFn>,
+        g: Box<TextFn>,
+    },
+
+    Train3 {
+        f: Box<TextFn>,
+        g: Box<TextFn>,
+        h: Box<TextFn>,
+    },
 }
 
 #[derive(Debug, Clone, PartialEq)]