Catching Exceptions

Exceptions can be caught with standard try ... catch blocks like in this example. There is a bug in our return8() function that is discovered by the T6.eq() method. Since we caught the error, the script continues to run normally.

Installation

Follow these steps to create a new project workspace and install the t6 dependency to run this example.

# Create and open project folder
mkdir Catching_Exceptions_demo
cd Catching_Exceptions_demo
# Initialize project and install dependencies
npm init -y
npm i t6@1.2.1
# Create and open source file
touch "Catching Exceptions.mjs"
open "Catching Exceptions.mjs"
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Source

Copy and paste this source code into Catching Exceptions.mjs.

import * as T6 from 't6';

// Oops! There was a logic
// error in returns8()!
function returns8() {
    return 9;
}

try {
    // This test will fail
    T6.eq(returns8(), 8);
} catch (e) {
    console.log(e.message);
}

console.log('...Still processing...');
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Output

In Catching_Exceptions_demo/, execute Catching Exceptions.mjs with NodeJS to generate an output.

node "Catching Exceptions.mjs"
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You should expect to see an output similar to the one below.

Exception found in test #1! The test value of 9 was not equal to the expected value of 8.
...Still processing...
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