From b66b4f66686d18fa2defe9cbd0b4168a180deb29 Mon Sep 17 00:00:00 2001
From: janis <janis@nirgendwo.xyz>
Date: Fri, 12 Jun 2026 00:22:18 +0200
Subject: [PATCH] fix let, let*

---
 stages/lisp0/lisp.asm | 33 ++++++++++++++-------------------
 stages/lisp0/lisp.rs  |  2 +-
 2 files changed, 15 insertions(+), 20 deletions(-)

diff --git a/stages/lisp0/lisp.asm b/stages/lisp0/lisp.asm
index 453953d..636dda5 100644
--- a/stages/lisp0/lisp.asm
+++ b/stages/lisp0/lisp.asm
@@ -615,48 +615,45 @@ p_if:
 ;; (Env, (var val), Env) -> Env
 ;; $rdi = acc-env, $rsi = (var val), $rdx = genv
 p_let_inner:
-    sub rsp, 24
+    sub rsp, 16
     mov qword [rsp], rdi        ; acc-env
     mov qword [rsp + 8], rsi    ; (var val)
-    mov qword [rsp + 16], rdx    ; genv
+    mov rdi, rsi
     call get_cdr
-    mov rdi, rax
+    mov rdi, rax                ; (val . nil)
     call get_car
-    mov rdi, rax
-    mov rsi, qword [rsp + 16]    ; genv
+    mov rdi, rax                ; val
+    mov rsi, rdx                ; genv
     call eval
     mov rsi, rax                ; val
     mov rdi, qword [rsp + 8]    ; (var val)
     call get_car
     mov rdi, rax                ; var
-    call cons
-    mov rdi, rax
-    mov rsi, qword [rsp]        ; acc-env
-    call cons
-    add rsp, 24
+    mov rdx, qword [rsp]        ; acc-env
+    call prepend                ; ((var . val) . acc-env)
+    add rsp, 16
     ret
 
 ;; (Env, (var val), Env) -> Env
 ;; $rdi = acc-env, $rsi = (var val), $rdx = genv
 p_let_star_inner:
-    sub rsp, 24
+    sub rsp, 16
     mov qword [rsp], rdi        ; acc-env
     mov qword [rsp + 8], rsi    ; (var val)
+    mov rdi, rsi
     call get_cdr
     mov rdi, rax
     call get_car
     mov rdi, rax
-    mov rsi, qword [rsp]    ; genv
+    mov rsi, qword [rsp]        ; acc-env
     call eval
     mov rsi, rax                ; val
     mov rdi, qword [rsp + 8]    ; (var val)
     call get_car
     mov rdi, rax                ; var
-    call cons
-    mov rdi, rax
-    mov rsi, qword [rsp]        ; acc-env
-    call cons
-    add rsp, 24
+    mov rdx, qword [rsp]        ; acc-env
+    call prepend                ; ((var . val) . acc-env)
+    add rsp, 16
     ret
     
 
@@ -1756,8 +1753,6 @@ prepend:
     call cons
     ret
 
-
-
 ;; PRIMITIVES
 
 ;; returns 1 if the object in $rdi is nil, 0 otherwise
diff --git a/stages/lisp0/lisp.rs b/stages/lisp0/lisp.rs
index a5aa396..609e40b 100644
--- a/stages/lisp0/lisp.rs
+++ b/stages/lisp0/lisp.rs
@@ -154,7 +154,7 @@ fn test_parse_list() {
     let env = unsafe { *ENV_INIT };
     println!("env: {:?}\n", env);
 
-    let input = b"((eval (define succ (lambda (x) (+ x 1)))) 4)";
+    let input = b"(let ((x 10) (y 20)) (+ x y))";
     let mut src = Source::from(&input[..]);
     let sexp = unsafe { parse_next_token(&raw mut src) };
     println!("> {:?}", sexp);