From 8b567f537becc7f69b02af774f782f8a5abe8f84 Mon Sep 17 00:00:00 2001
From: Osvaldo Dias dos Santos <osvaldo.msdsantos@yahoo.com>
Date: Fri, 20 Jan 2023 22:13:02 +0100
Subject: [PATCH] Add solution file

---
 1-js/99-js-misc/02-eval/1-eval-calculator/solution.md | 11 +++++++++++
 1 file changed, 11 insertions(+)
 create mode 100644 1-js/99-js-misc/02-eval/1-eval-calculator/solution.md

diff --git a/1-js/99-js-misc/02-eval/1-eval-calculator/solution.md b/1-js/99-js-misc/02-eval/1-eval-calculator/solution.md
new file mode 100644
index 000000000..24d40c9b8
--- /dev/null
+++ b/1-js/99-js-misc/02-eval/1-eval-calculator/solution.md
@@ -0,0 +1,11 @@
+Let's use `eval` to calculate the maths expression:
+
+```js demo run
+let expr = prompt("Type an arithmetic expression?", '2*3+2');
+
+alert( eval(expr) );
+```
+
+The user can input any text or code though.
+
+To make things safe, and limit it to arithmetics only, we can check the `expr` using a [regular expression](info:regular-expressions), so that it only may contain digits and operators.