Week 5: End-of-Course Graded Assessment

Lab Instructions: Little Lemon Receipt Maker

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Assignment Instructions

In this exercise, you will work with some data provided as an array of objects, listing information about dishes available in the Little Lemon restaurant.

Step 1: In the function getPrices(), give it the parameter of taxBoolean.

Step 2: Inside the getPrices() function, code a for loop that will loop over all the objects inside the dishData array.

Step 3: Inside the for loop, declare a finalPrice variable, without assigning it a value.

Step 4: Still inside the for loop, add an if condition, checking that the taxBoolean is set to true. Inside the if block, multiply the following: * the price of the currently looped-over object from the dishData array, and * the tax value. Assign the multiplied value to the finalPrice variable.

Step 5: Right after the if condition, add an else if, checking if the value of taxBoolean is false. Inside this condition’s block, assign the currently looped-over dish price property in the dishData array to the finalPrice variable.

Step 6: Code the else case, and inside of it, add two lines of code:

A console log of the string:

• “You need to pass a boolean to the getPrices call!”
• return (to “jump out” of the further function execution)
  

Step 7: After all the conditional’s statements, but still inside the for loop, code another console log with four arguments:

1. The string "Dish: "
2. The value of currently looped-over dish object’s name property
3. The string "Price: $"
4. The value of the finalPrice variable
   

Step 8: You’re finshed with the getPrices() function, and now you’re ready to code another function. Give the getDiscount() function, two parameters: the taxBoolean and the guests parameter.

Step 9: Inside the getDiscount() function, on the very first line of its body, invoke the getPrices() function, passing it the taxBoolean as an argument.

Step 10: On another line, you need to implement your defensive coding skills, and check that the type of the guests parameter is ‘number’ and that the value of the guests variable is greater than zero and less than 30. If all these conditions return true, code the body of the conditional as described in the next step. If they don’t all return true, code the body of the else conditional as instructed in step 12.

Step 11: Inside the if statment, declare a new variable, named discount, and set it to 0. On the next line, add another if…else if: in the first if, you’ll check that the value of the guests variable is less than 5. If that’s the case, reassign the value of the discount variable to 5;

• Inside the else if condition, check that the value of the guests variable is greater than or equal to 5 – if that’s the case, reassign the discount variable to 10.
• Console log the following after closing your else-if statement: 'Discount is: $' + discount);

Step 12: In the else condition, console log the following string: 'The second argument must be a number between 0 and 30'. Since you’ve finished declaring both the getPrices() and the getDiscount() functions, you can now invoke the getDiscount() function several times, with various combinations of arguments, to check the behavior.

Here are two examples:

• getDiscount(true, 2)
• getDiscount(false, 10)

What happens when you don’t pass-in any arguments?

What happens when you pass values that are not expected?

const a = 10;
const b = 5;
if(a == 7 || b == 5) {
    console.log("Green");
} else {
    console.log("Blue");
}

Green

That’s correct. The logical OR operator results in the condition being true. Therefore, the code inside the if statement will execute and Green will be output.

var x = true;
x = 23;
console.log(x);

23

That’s correct! The x variable is re-assigned the value 23. Therefore, 23 is output by the code.

var x = 0 != 1;

Boolean

That’s correct! 0 != 1 will result in a true value which is a boolean.

var x = 20;

if(x >= 10) {
    console.log("Apple");
} else if(x <= 5) {
    console.log("Pear");
} else {
    console.log("Orange");
}

Apple

That’s correct! The x variable has the value of 20, therefore the first condition succeeds. The code inside the if statement will run and output Apple.

var result = 0;

for(var i = 0; i < 5; i++) {
    result += 2;
}

console.log(result);

10

That’s correct! The loop will run 5 times and each time add 2 to the result variable. Therefore, 10 will be output.

var result;
console.log(result);
result = 7;

7

function(a,b) {
    return a + b
}

The function name.

Well done. When coding function declarations, you need to give them a name.

var car = { mileage: 200 }
var carMileage = 100
console.log(car.mileage)

200

Well done. You can access the mileage property on the car object using the dot notation.

var veggies = ['parsley', 'carrot']
console.log(veggies[2])

undefined

Well done. Trying to output the third item in the veggies array, using the syntax veggies [2] will console log undefined because the veggies array has only 2 items, “parsley” and “carrot”.

A string describing the type of event (such as, “click”).

Well done. The first argument to pass to the addEventListener function is the type of the event you’re listening for, such as “click”.

With document.createElement(‘h2’)

Well done. You create new elements on the document object using the createElement function.

function addFive(val) {
  return val + 5;
};
module.exports = addFive;

It defines the addFive function and exports it as a Node module so that it can be used in other files.

Well done. It’s a way to export the addFive function as a module that can be used elsewhere.