remove duplicate let declaration of parameter str

Author: remimarcelle

Sprint-2/1-key-errors/0.js

@@ -1,13 +1,29 @@
 // Predict and explain first...
 //  =============> write your prediction here
+// I think that there will be a SyntaxError because str is already
+// declared as a parameter, and I am trying to re-declare it as
+// a variable with let inside the function. This is not allowed in
+// Javascript.
 
 // call the function capitalise with a string input
 // interpret the error message and figure out why an error is occurring
 
+// function capitalise(str) {
+//  let str = `${str[0].toUpperCase()}${str.slice(1)}`;
+//  return str;
+// }
+
+// =============> write your explanation here
+// You can't use let to declare a variable with the same name
+// as a parameter in the same function. The parameter str is 
+// already declared, so when you try to declare it again with let,
+// it causes a SyntaxError. To fix this, you can either remove
+// let and just assign a new value to str, or you can use a different
+// variable name for the capitalised string.
+// =============> write your new code here
 function capitalise(str) {
-  let str = `${str[0].toUpperCase()}${str.slice(1)}`;
+  str = `${str[0].toUpperCase()}${str.slice(1)}`;
   return str;
 }
 
-// =============> write your explanation here
-// =============> write your new code here
+console.log(capitalise("hello"));