From 684f59c48cb865ecf935be47d6f59e94f1e77961 Mon Sep 17 00:00:00 2001
From: Hojun-Cho <ghwns6743@gmail.com>
Date: Wed, 27 May 2026 02:03:04 +0900
Subject: [PATCH] lib/strconv: decimal.ww header documents i_sz/lowbit_lit
 hoist sub-cases (#32 c2)
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Add a sub-bullet to the 8-spelling-divergences list documenting two
implementation sub-cases reviewer-fold3 surfaced during the 07e57ff
decimal.ha port: (1) `i_sz` per-iteration size-cast hoist inside
leftshift_newdigits' for-loop (decimal.ww:93); (2) `lowbit_lit`
stepwise boolean decomposition in should_round_up (decimal.ww:242)
dodging ww parser precedence on Hare's `(nd > 0 && d.digits[nd - 1]
& 1 != 0)` (ref/hare/strconv/decimal.ha:158). Both are in-file
instances of the documented hoist+restructure patterns — rule-9
doc-completeness, not new divergence. Combined.ww regen for
lib/strconv (compiler-imported into w6c + wwdump + smoke) uses the
build's include paths (`-I lib/ww -I lib/ww/lex -I lib/ww/parse
-I selfhost/cmd/wcc`) for transitive import closure; bare `ww build`
without these flags produces truncated output (reviewer-32c2 +
reviewer-fold3 both hit this).
---
 lib/strconv/decimal.ww               | 7 +++++++
 selfhost/cmd/w6c/main.combined.ww    | 7 +++++++
 selfhost/cmd/wwdump/main.combined.ww | 7 +++++++
 selfhost/test/smoke.combined.ww      | 7 +++++++
 4 files changed, 28 insertions(+)

diff --git a/lib/strconv/decimal.ww b/lib/strconv/decimal.ww
index a70babc9..c89fccf0 100644
--- a/lib/strconv/decimal.ww
+++ b/lib/strconv/decimal.ww
@@ -24,6 +24,13 @@
 //     → ww requires a `{}` block body throughout.
 //   - Hare bare `assert(cond)` builtin → `os.assert(cond, msg)`;
 //     wwstage cgen has no `assert` intercept (deferred fold).
+//   - In-file instances of the above hoist pattern: `i_sz` (line 93)
+//     hoists a per-iteration size cast out of a for-loop comparison
+//     (bullet 3 sub-case — the size-cast hoist applied inside a loop
+//     body, not just at function entry); `lowbit_lit` (line 242)
+//     decomposes Hare's `(nd > 0 && d.digits[nd - 1] & 1 != 0)` into
+//     a stepwise boolean local to dodge ww parser precedence on mixed
+//     `&` / `&&` / `!=` within a single expression.
 //
 // CGEN class closures consumed (post-prereqs):
 //   - #131 (4acab6e) — `len(d.digits)` compile-time-folds cs==ww
diff --git a/selfhost/cmd/w6c/main.combined.ww b/selfhost/cmd/w6c/main.combined.ww
index b38703c8..4616c501 100644
--- a/selfhost/cmd/w6c/main.combined.ww
+++ b/selfhost/cmd/w6c/main.combined.ww
@@ -2730,6 +2730,13 @@ export fn rpad(s: str, p: rune, maxlen: i32) str = {
 //     → ww requires a `{}` block body throughout.
 //   - Hare bare `assert(cond)` builtin → `os.assert(cond, msg)`;
 //     wwstage cgen has no `assert` intercept (deferred fold).
+//   - In-file instances of the above hoist pattern: `i_sz` (line 93)
+//     hoists a per-iteration size cast out of a for-loop comparison
+//     (bullet 3 sub-case — the size-cast hoist applied inside a loop
+//     body, not just at function entry); `lowbit_lit` (line 242)
+//     decomposes Hare's `(nd > 0 && d.digits[nd - 1] & 1 != 0)` into
+//     a stepwise boolean local to dodge ww parser precedence on mixed
+//     `&` / `&&` / `!=` within a single expression.
 //
 // CGEN class closures consumed (post-prereqs):
 //   - #131 (4acab6e) — `len(d.digits)` compile-time-folds cs==ww
diff --git a/selfhost/cmd/wwdump/main.combined.ww b/selfhost/cmd/wwdump/main.combined.ww
index a5714279..42eced79 100644
--- a/selfhost/cmd/wwdump/main.combined.ww
+++ b/selfhost/cmd/wwdump/main.combined.ww
@@ -753,6 +753,13 @@ export fn exists(path: str) bool = {
 //     → ww requires a `{}` block body throughout.
 //   - Hare bare `assert(cond)` builtin → `os.assert(cond, msg)`;
 //     wwstage cgen has no `assert` intercept (deferred fold).
+//   - In-file instances of the above hoist pattern: `i_sz` (line 93)
+//     hoists a per-iteration size cast out of a for-loop comparison
+//     (bullet 3 sub-case — the size-cast hoist applied inside a loop
+//     body, not just at function entry); `lowbit_lit` (line 242)
+//     decomposes Hare's `(nd > 0 && d.digits[nd - 1] & 1 != 0)` into
+//     a stepwise boolean local to dodge ww parser precedence on mixed
+//     `&` / `&&` / `!=` within a single expression.
 //
 // CGEN class closures consumed (post-prereqs):
 //   - #131 (4acab6e) — `len(d.digits)` compile-time-folds cs==ww
diff --git a/selfhost/test/smoke.combined.ww b/selfhost/test/smoke.combined.ww
index 3c8763e6..ed340db3 100644
--- a/selfhost/test/smoke.combined.ww
+++ b/selfhost/test/smoke.combined.ww
@@ -753,6 +753,13 @@ export fn exists(path: str) bool = {
 //     → ww requires a `{}` block body throughout.
 //   - Hare bare `assert(cond)` builtin → `os.assert(cond, msg)`;
 //     wwstage cgen has no `assert` intercept (deferred fold).
+//   - In-file instances of the above hoist pattern: `i_sz` (line 93)
+//     hoists a per-iteration size cast out of a for-loop comparison
+//     (bullet 3 sub-case — the size-cast hoist applied inside a loop
+//     body, not just at function entry); `lowbit_lit` (line 242)
+//     decomposes Hare's `(nd > 0 && d.digits[nd - 1] & 1 != 0)` into
+//     a stepwise boolean local to dodge ww parser precedence on mixed
+//     `&` / `&&` / `!=` within a single expression.
 //
 // CGEN class closures consumed (post-prereqs):
 //   - #131 (4acab6e) — `len(d.digits)` compile-time-folds cs==ww