From fbef762f7b3fb10eec03deb7772d34460e867a1d Mon Sep 17 00:00:00 2001
From: seonghobae <8172694+seonghobae@users.noreply.github.com>
Date: Tue, 1 Sep 2026 04:07:43 +0000
Subject: [PATCH 1/3] =?UTF-8?q?=E2=9A=A1=20Bolt:=20Optimize=20list=20itera?=
 =?UTF-8?q?tion=20with=20vapply?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Replaced `sapply` with `vapply` in `R/llcont.R` when iterating over `mispatts` to find the maximum number of rows.
In R codebases, `sapply` involves significant overhead to deduce and simplify the return type dynamically. Using `vapply` with a predefined return type avoids this overhead.
---
 .jules/bolt.md | 3 +++
 R/llcont.R     | 3 ++-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/.jules/bolt.md b/.jules/bolt.md
index f658475..604ecab 100644
--- a/.jules/bolt.md
+++ b/.jules/bolt.md
@@ -15,3 +15,6 @@
 ## 2024-05-15 - [R Performance: ifelse Overhead]
 **Learning:** In R, ifelse evaluates both true and false branches entirely before subsetting, which is very inefficient for vector operations.
 **Action:** Optimize this by preallocating with res <- Y * 0 to preserve attributes and using vectorized subsetting like if any cond res subset <- ...
+## 2026-09-01 - Avoid sapply overhead on lists
+**Learning:** In R codebases, using `sapply` over a list involves significant overhead to deduce and simplify the return type.
+**Action:** When the return type and length are known, prefer `vapply(..., FUN.VALUE = type)` over `sapply(...)` for better performance and safety.
diff --git a/R/llcont.R b/R/llcont.R
index d8e496a..ce4ccd2 100644
--- a/R/llcont.R
+++ b/R/llcont.R
@@ -407,7 +407,8 @@ llcont.lavaan <- function(x, ...){
   if(tolower(lavInspect(x, "options")$missing) == "ml.x") stop("cannot handle lavaan models with missing='ml.x'. consider using missing='ml'.", call. = FALSE)
   mispatts <- lavInspect(x, "patterns")
   if(any(class(mispatts) == "list")){
-    npatts <- max(sapply(mispatts, nrow))
+    ## Bolt: replaced sapply with vapply to avoid type deduction overhead
+    npatts <- max(vapply(mispatts, nrow, numeric(1)))
   } else {
     npatts <- nrow(mispatts)
   }

From 85b95b178e920b885c68a7aa3199240c21549475 Mon Sep 17 00:00:00 2001
From: seonghobae <8172694+seonghobae@users.noreply.github.com>
Date: Tue, 1 Sep 2026 07:40:28 +0000
Subject: [PATCH 2/3] =?UTF-8?q?=E2=9A=A1=20Bolt:=20Optimize=20list=20itera?=
 =?UTF-8?q?tion=20with=20vapply?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Replaced `sapply` with `vapply` in `R/llcont.R` when iterating over `mispatts` to find the maximum number of rows.
In R codebases, `sapply` involves significant overhead to deduce and simplify the return type dynamically. Using `vapply` with a predefined return type avoids this overhead.

From 7b9d3a89c14d567d86b23b26bf61e1d4d1ed64eb Mon Sep 17 00:00:00 2001
From: seonghobae <8172694+seonghobae@users.noreply.github.com>
Date: Tue, 1 Sep 2026 11:44:29 +0000
Subject: [PATCH 3/3] =?UTF-8?q?=E2=9A=A1=20Bolt:=20Optimize=20list=20itera?=
 =?UTF-8?q?tion=20with=20vapply?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Replaced `sapply` with `vapply` in `R/llcont.R` when iterating over `mispatts` to find the maximum number of rows.
In R codebases, `sapply` involves significant overhead to deduce and simplify the return type dynamically. Using `vapply` with a predefined return type avoids this overhead.