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POunderstanding exception handling in JavaScript: get different output when changed the place of try/catch block
 

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  1. POunderstanding exception handling in JavaScript: get different output when changed the place of try/catch block
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    <p>I am new to learning JavaScript and sort of stuck up while learning exception handling. I have understood the thing that whenever an exception occurs , it is thrown using "throw" keyword and similarly it is caught using "catch" block.</p> <p>But what I am unable to understand is that , I have a small , simple code that demonstrates simple Exception handling technique, and in that code whenever I change the place of the catch block, I get different outputs. Here is the simple code and its different o/p s depending upon where I place the catch block.</p> <pre><code>function lastElement(array) { if (array.length &gt; 0) return array[array.length - 1]; else throw "Can not take the last element of an empty array."; } function lastElementPlusTen(array) { return lastElement(array) + 10; } try { print(lastElementPlusTen([])); } catch (error) { print("Something went wrong: ", error); } </code></pre> <p>the o/p that I get here is as expected :</p> <pre><code>Something went wrong: Can not take the last element of an empty array. </code></pre> <p>now when I add the try/catch block around the function lastElementPlusTen: like this</p> <pre><code>function lastElement(array) { if (array.length &gt; 0) return array[array.length - 1]; else throw "Can not take the last element of an empty array."; } try { function lastElementPlusTen(array) { return lastElement(array) + 10; } } catch (error) { print("Something went wrong: ", error); } print(lastElementPlusTen([])); </code></pre> <p>now the o/p that I get here is :</p> <pre><code>Exception: "Can not take the last element of an empty array." </code></pre> <p>the "something went wrong" from the catch block is not printed.</p> <p>why is this so??similarly when I place the try/catch block around different pieces of code (for ex: around the first function , body of the lastElementPlusTen function etc) I get different o/p s. why is this happening. How does exception handling work??</p>
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    1. COWhat JavaScript environment are you using? I'm just wondering as it doesn't seem to be a browser environment.
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    2. COyes ! i am studying from "eloquent javascript" so i am using the console provided by them
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      1. USneerajDorle
 

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