Merge pull request GitbookIO#41 from Hermanya/master

Declaring Functions notes

Author: SamyPesse

functions/declare.md

@@ -8,6 +8,8 @@ function double(x) {
 }
 ```
 
+>*Note:* the function above **may** be referenced before it has been defined.
+
 Functions are also values in JavaScript; they can be stored in variables (just like numbers, strings, etc ...) and given to other functions as arguments :
 
 ```javascript
@@ -16,6 +18,8 @@ var double = function(x) {
 };
 ```
 
+>*Note:* the function above **may not** be referenced before it is defined, just like any other variable. 
+
 ---
 
 Declare a function named `triple` that takes an argument and returns its triple.