From 683d0f4dbed09673107de16ec1d382491ad97535 Mon Sep 17 00:00:00 2001
From: Michael Schimmel <schimmel@mycelium.de>
Date: Tue, 24 Feb 2026 10:10:47 +0100
Subject: [PATCH] Simplify tuple flattening and destructuring

The `flatten_tuple` function was unnecessarily recursive. It can now
simply return the elements of the tuple directly. The VM's destructuring
logic has been updated to handle nested destructuring more efficiently.
A new integration test case for multi-level destructuring has been
added.
---
 examples/destructuring.myc      |  4 ++--
 examples/tuple-struct.myc       | 12 ++++++++++++
 src/ast/compiler/specializer.rs |  8 +-------
 src/ast/vm.rs                   | 10 +++++++++-
 src/integration_test.rs         | 21 +++++++++++++++++++++
 5 files changed, 45 insertions(+), 10 deletions(-)
 create mode 100644 examples/tuple-struct.myc

diff --git a/examples/destructuring.myc b/examples/destructuring.myc
index 23ad46e..a40a632 100644
--- a/examples/destructuring.myc
+++ b/examples/destructuring.myc
@@ -1,5 +1,5 @@
-;; Benchmark: 969ns
-;; Benchmark-Repeat: 2078
+;; Benchmark: 969ns
+;; Benchmark-Repeat: 2078
 ;; Comprehensive Destructuring Test
 ;; Covers: Nested tuples, mixed params, dynamic passing
 
diff --git a/examples/tuple-struct.myc b/examples/tuple-struct.myc
new file mode 100644
index 0000000..567811c
--- /dev/null
+++ b/examples/tuple-struct.myc
@@ -0,0 +1,12 @@
+(do
+     (def pipe (fn [conf]
+       (do
+          (def [str s] conf)
+          (def [f ss] s)
+          ["Symbol:" str "field:" f "id:" ss]
+       )
+      )
+     )
+
+     (pipe ["btc" [:close "cls"]])
+   )
\ No newline at end of file
diff --git a/src/ast/compiler/specializer.rs b/src/ast/compiler/specializer.rs
index 197fe39..6d35082 100644
--- a/src/ast/compiler/specializer.rs
+++ b/src/ast/compiler/specializer.rs
@@ -308,13 +308,7 @@ impl Specializer {
 
     fn flatten_tuple(&self, node: AnalyzedNode) -> Vec<AnalyzedNode> {
         match node.kind {
-            BoundKind::Tuple { elements } => {
-                let mut flat = Vec::new();
-                for el in elements {
-                    flat.extend(self.flatten_tuple(el));
-                }
-                flat
-            }
+            BoundKind::Tuple { elements } => elements,
             _ => vec![node],
         }
     }
diff --git a/src/ast/vm.rs b/src/ast/vm.rs
index a8ba6a4..ab23eb4 100644
--- a/src/ast/vm.rs
+++ b/src/ast/vm.rs
@@ -416,7 +416,15 @@ impl VM {
                                 {
                                     self.stack.extend(arg_vals);
                                 } else {
-                                    self.unpack(&closure.parameter_node, &arg_vals, &mut 0)?;
+                                    // Map each parameter pattern to the provided arguments
+                                    if let BoundKind::Tuple { elements } = &closure.parameter_node.kind {
+                                        let mut offset = 0;
+                                        for el in elements {
+                                            self.unpack(el, &arg_vals, &mut offset)?;
+                                        }
+                                    } else {
+                                        self.unpack(&closure.parameter_node, &arg_vals, &mut 0)?;
+                                    }
                                 }
                                 let result = self.eval_internal(obs, &closure.exec_node);
                                 self.frames.pop();
diff --git a/src/integration_test.rs b/src/integration_test.rs
index 82cfc59..a817561 100644
--- a/src/integration_test.rs
+++ b/src/integration_test.rs
@@ -369,4 +369,25 @@ mod tests {
             }
         }
     }
+
+    #[test]
+    fn test_multi_level_destructuring() {
+        let env = Environment::new();
+        let source = "(do
+          (def pipe (fn [conf]
+            (do
+               (def [str s] conf)
+               (def [f ss] s)
+               [\"Symbol:\" str \"field:\" f \"id:\" ss]
+            )
+           )
+          )
+          (pipe [\"btc\" [:close \"cls\"]]))";
+
+        let res = env.run_script(source).unwrap();
+        assert_eq!(
+            format!("{}", res),
+            "[\"Symbol:\" \"btc\" \"field:\" :close \"id:\" \"cls\"]"
+        );
+    }
 }