Added Get Function Code

Author: khianvictorycalderon

Get_Function_Code.js

@@ -0,0 +1,18 @@
+
+function getFunctionCode(functionName) {
+    return typeof functionName === "function" ? functionName.toString() : "The argument is not a function.";
+}
+
+// Example
+function Add(a, b) {
+    return a + b;
+}
+function Subtract(x, y) {
+    return x - y;
+}
+
+// Using custom function
+console.log(getFunctionCode(Add));
+
+// Using built-in function
+console.log(Subtract.toString());