docs: add control flow braces rule to coding style

1 files changed, 19 insertions, 0 deletions

diff --git a/doc/CODING_STYLE.md b/doc/CODING_STYLE.md
index 57d4478..ba3fcb5 100644
--- a/doc/CODING_STYLE.md
+++ b/doc/CODING_STYLE.md
@@ -108,6 +108,25 @@ Use designated initializers, not field-by-field assignment.
 
 ---
 
+## Control Flow Braces
+
+**Rule:** Multi-line `for` or `if` statements must use curly braces.
+
+### Good
+```cpp
+for (int i = 0; i < 10; ++i) {
+  do_something(i);
+}
+```
+
+### Bad
+```cpp
+for (int i = 0; i < 10; ++i)
+  do_something(i);
+```
+
+---
+
 ## Class Keywords Indentation
 
 ```cpp