exercise-typescript-functions.md

Practice: TypeScript functions

Intro

• For this exercise, you can work on your local environment (if you have the TypeScript compiler installed).

• Or, if you prefer, you can work on an online editor like Stackblitz. For example, you can write your TypeScript code here:
  

https://stackblitz.com/edit/typescript-vkcluy?file=index.ts

Iteration 1 - Create a function greetUser()

Requirements:

• Name of the function: greetUser
• Parameters:
  • userName (a string) - required.
  • languageCode (a string) - optional.
• Return value:
  • If language is de, your function should return "Guten Morgen, [userName]!".
  • If language is es, your function should return "Buenos días, [userName]!".
  • If language is en (or no language is provided), your function should return "Good morning, [userName]!".

Iteration 2 - Create a function calcCircleArea()

Requirements:

• Name of the function: calcCircleArea
• Parameters:
  • radius (a number) - required.
• Return value:
  • Return the area of the circle, calculated using the formula: PI * radius * radius
• Notes:
  • You may need to do some research to get the value of PI in JS.
  • The returned value should be rounded to two decimal places.
  • If a radius of less than or equal to 0 is provided, return null indicating an invalid radius.

Bonus - Create a function binaryToDecimal()

Requirements:

• Name of the function: binaryToDecimal
• Parameters:
  • binaryString (a string) - required. The string should represent a binary number (e.g., '1010', '1101', '111111101').
• Return value:
  • The function should return the decimal equivalent of the binary number.
  • If the provided string is not a valid binary number (contains characters other than '0' and '1'), return null indicating an invalid input.

Other bonus ideas:

• practice TypeScript syntax with traditional functions and/or arrow functions
• implement a function calculateRectangleArea()
• implement a function calculateTriangleArea()

Solution: https://stackblitz.com/edit/typescript-kmbka6?file=index.ts