conlang: Unify binding operations!

This breaks out the pattern matching/unification algorithm from cl-interpret/interpret.rs to cl-interpret/pattern.rs

TODO: pattern destructuring in const, static :^)

compiler/cl-ast/src/ast.rs

@@ -153,7 +153,7 @@ pub struct Function {
 #[derive(Clone, Debug, PartialEq, Eq, Hash)]
 pub struct Param {
     pub mutability: Mutability,
-    pub name: Sym,
+    pub bind: Pattern,
 }
 
 /// A user-defined product type

compiler/cl-ast/src/ast_impl.rs

@@ -194,8 +194,8 @@ mod display {
 
     impl Display for Param {
         fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-            let Self { mutability, name } = self;
-            write!(f, "{mutability}{name}")
+            let Self { mutability, bind } = self;
+            write!(f, "{mutability}{bind}")
         }
     }
 
@@ -474,11 +474,11 @@ mod display {
                 Pattern::Tuple(patterns) => separate(patterns, ", ")(f.delimit(INLINE_PARENS)),
                 Pattern::Array(patterns) => separate(patterns, ", ")(f.delimit(INLINE_SQUARE)),
                 Pattern::Struct(path, items) => {
-                    write!(f, "{path}: ")?;
-                    let f = &mut f.delimit(BRACES);
+                    write!(f, "{path} ")?;
+                    let f = &mut f.delimit(INLINE_BRACES);
                     for (idx, (name, item)) in items.iter().enumerate() {
                         if idx != 0 {
-                            f.write_str(",\n")?;
+                            f.write_str(", ")?;
                         }
                         write!(f, "{name}")?;
                         if let Some(pattern) = item {
@@ -639,7 +639,7 @@ mod display {
     impl Display for Structor {
         fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
             let Self { to, init } = self;
-            write!(f, "{to}: ")?;
+            write!(f, "{to} ")?;
             separate(init, ", ")(f.delimit(INLINE_BRACES))
         }
     }

compiler/cl-ast/src/ast_visitor/fold.rs

@@ -111,8 +111,8 @@ pub trait Fold {
         }
     }
     fn fold_param(&mut self, p: Param) -> Param {
-        let Param { mutability, name } = p;
-        Param { mutability: self.fold_mutability(mutability), name: self.fold_sym(name) }
+        let Param { mutability, bind } = p;
+        Param { mutability: self.fold_mutability(mutability), bind: self.fold_pattern(bind) }
     }
     fn fold_struct(&mut self, s: Struct) -> Struct {
         let Struct { name, kind } = s;

compiler/cl-ast/src/ast_visitor/visit.rs

@@ -89,9 +89,9 @@ pub trait Visit<'a>: Sized {
         }
     }
     fn visit_param(&mut self, p: &'a Param) {
-        let Param { mutability, name } = p;
+        let Param { mutability, bind } = p;
         self.visit_mutability(mutability);
-        self.visit_sym(name);
+        self.visit_pattern(bind);
     }
     fn visit_struct(&mut self, s: &'a Struct) {
         let Struct { name, kind } = s;