Quartz 4

README

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Type Annotations With Arrays

Type annotations with arrays allow you to specify the expected data types of the array elements, ensuring type safety in your code.

// Annotating an array of strings
let fruits: string[] = ["apple", "banana", "cherry"];
 
// Using a loop to process each element in the array
for (let i = 0; i < fruits.length; i++) {
  console.log(`Fruit: ${fruits[i].toUpperCase()}`);
}
  1. We annotate the fruits array as an array of strings.
  2. We use a for loop to iterate over the fruits array and display each fruit in uppercase letters.

Type Annotations With Multidimensional Arrays

let arrayOne: number[] = [1, 2, 3, 4, 5];
let arrayTwo: string[] = ["A", "B", "C"];
let arrayThree: (string | number)[] = [1, 2, 3, 4, "A", "B", "C"];

In this code:

  1. arrayOne is declared as an array of numbers, annotated with the type number[]. This means it can only contain numeric values.
  2. arrayTwo is declared as an array of strings, annotated with the type string[]. It should only contain string values.
  3. arrayThree is declared as an array that can hold elements of either type string or number, annotated with (string | number)[]. This array allows for a mixture of numeric and string values within the same array.

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