From 7d7d324454f3081c3112163067d331e38ac21755 Mon Sep 17 00:00:00 2001
From: SaintFTS <152052965+SaintFTS@users.noreply.github.com>
Date: Mon, 3 Mar 2025 23:10:21 +0500
Subject: [PATCH] Update 105-macros.md
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Added an example of dangerous macroses. The example is taken from Bjarne Stroustrup's C++11 4th Edition book, §12.6.
---
 .../cpp/content/109-language-concepts/105-macros.md    | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/data/roadmaps/cpp/content/109-language-concepts/105-macros.md b/src/data/roadmaps/cpp/content/109-language-concepts/105-macros.md
index f607bba49..e501b543b 100644
--- a/src/data/roadmaps/cpp/content/109-language-concepts/105-macros.md
+++ b/src/data/roadmaps/cpp/content/109-language-concepts/105-macros.md
@@ -35,6 +35,14 @@ This macro defines a function-like macro `SQUARE` that calculates the square of
 ```cpp
 int square_of_five = SQUARE(5); // expands to ((5) * (5))
 ```
+**CAUTION!**
+
+The following macro may seem to be the same as the one above, but this version can lead to unexpected results:
+```cpp
+#define SQUARE(x) (x*x); // DANGEROUS!!!
+#define PI 3.14159;
+const double val = SQUARE(PI+2); // expands to (PI+2*PI+2), and equals to (3*PI+2)
+```
 
 ## Conditional Compilation
 
@@ -52,4 +60,4 @@ Example:
 #endif
 ```
 
-This example demonstrates how you can use macros to control the parts of code that are being compiled, depending on the presence or absence of a macro definition.
\ No newline at end of file
+This example demonstrates how you can use macros to control the parts of code that are being compiled, depending on the presence or absence of a macro definition.