workshopsoft/ludic
2
0
Fork 0
Code Issues Pull requests Projects Releases 26 Packages Wiki Activity Actions

Phase 6f: let = immutable, var = mutable (binding-only)

Browse source 
Bindings now signal mutability the way Rust/Swift do, instead of `let` meaning
"local" and `var` meaning "module-level":

  - `let x = e`  -> immutable binding; a later `x = …` is a compile error
    (`cannot assign to immutable 'x' … use var`).
  - `var x = e`  -> mutable binding, at local OR module scope (position decides
    scope; the keyword decides mutability).
  - `const`      -> unchanged (compile-time).

Immutability is of the *binding*, not the object: `let n = new Node; n.kind = 1`
is fine (mutation through the reference); only rebinding `n` is rejected. The
check lives in emit_assign — a direct `name =` whose target is a `let` local
(loc_mut == 0) errors; field/index targets and `var`/param/loop bindings are
unaffected.

Delivered as three reseeds so the self-hosting compiler never had to compile
source its own rules would reject:
  A) add `var` as a local statement + per-local mutability tracking (loc_mut),
     no enforcement;
  B) migrate every reassigned `let` -> `var` across the compiler, runtime and
     examples (337 declarations), driven by a per-function, string/comment-aware
     scan (binding targets only, never `x.f =` / `x[i] =`);
  C) turn on the check. bootstrap-cfree (compiler vs its own source) and every
     golden build (which splices the runtime) then proved zero reassigned `let`
     was missed anywhere.

Also folded in: removed leftover debug instrumentation in block() (a `cur=` /
print_int(777…) trace on the separator-error path) and fixed parse.ludic's stale
header comment (no more `struct`). Reseeded (21711 lines); C-free fixpoint holds;
goldens identical; 17/17; vocab + doc-fences clean.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
This commit is contained in:
Orkun ÇAKILKAYA 2026-08-27 23:52:59 +03:00
parent 573813609c
commit e1d7797e29
38 changed files with 2909 additions and 2778 deletions
Download patch file Download diff file Expand all files Collapse all files

8
selfhost/emit_decl.ludic
View file

@ -3,7 +3,7 @@
# ahead of it (see emit_alloca). Returns go through a %retval slot + `ret` label.
fn emit_params_sig(d: Node) -> void {
let i = 0
var i = 0
while i < len(d.kids) {
if i > 0 { emit(", ") }
emit(llty(d.kids[i].ty)); emit(" %arg_"); emit(d.kids[i].s)
@ -21,7 +21,7 @@ fn emit_fn(d: Node) -> void {
let rl = llty(ret_ty)
if not streq(rl, "void") { buf_puts(falloc, " %retval = alloca "); buf_puts(falloc, rl); buf_puts(falloc, "\n") }
# params: store each incoming argument into a stack slot
let i = 0
var i = 0
while i < len(d.kids) {
let p = d.kids[i]
let slot = emit_alloca(llty(p.ty))
@ -67,13 +67,13 @@ fn emit_main(d: Node) -> void {
fn emit_program() -> void {
head = buf_new()
code = buf_new()
loc_name = new []ptr; loc_reg = new []ptr; loc_ty = new []ptr
loc_name = new []ptr; loc_reg = new []ptr; loc_ty = new []ptr; loc_mut = new []int
brk_lbl = new []ptr; cnt_lbl = new []ptr
self_stk = new []ptr
mach_stk = new []Node
emit_header()
if has_ecs() { emit_ecs_storage() }
let i = 0
var i = 0
while i < len(prog) { if prog[i].kind == N_FN { emit_fn(prog[i]) }; i = i + 1 }
if has_ecs() { emit_ecs_allocator(); emit_snapshot() }
if has_ui() { emit_ui_build() }