9.TypeScript Tuples
TypeScript Tuples In the last chapter, you learn array in which you can store similar types of values in a single variable. But what if we want to store more than one data types values in a single array? Yes, typescript supports Tuples in which you can store more than one type of values and this is called Tuples in TypeScript. So, in Tuples represents a heterogeneous group of values. Or we can say, tuples helps us in storing multiple fields of different types. You can also pass tuples as a parameter in any function.
Syntax
var tuple_name = [val1,val2,val3,val4.. valn]
For Example
var basket= [200,"Biscit",23.50,”Jeans”];
Displaying values of Tuples Individual items in Tuple are called items. Since Tuples are arry, so we can access its value through its index.
Example: Simple Tuple
var basket= [200,"Biscit",23.50,”Jeans”];
console.log(basket[0])
console.log(basket[1])
console.log(basket[2])
If you look at above example, we have created a tuple, basket.This tuple
Declaring Empty Tuple
We can also declare empty Tuples and then we can fill its values.
Example :
var bags= [] // we have declared empty Tuple
bags[0] = 'Pencil' bags[1] = 500 bags[2] = 'Tiffin Box'
console.log(bags[0])
console.log(bags[1])
console.log(bags[2])
Output :
Tuple Functions Since tuples is a form of array that supports different functions. Same way, Tuples also support different array functions .Tuples in TypeScript supports various operations like pushing a new item, removing an item from the tuple, etc.
Example
var courses= ['Java',"C++","C","typeScript"];
console.log("Courses before push "+courses.length) // returns the tuple size
console.log("Items before pop "+courses.length)
console.log(courses.pop()+" popped from the tuple")
console.log("Course after pop "+courses.length)
courses.push('PHP') // append value to the tuple
console.log("Courses after push "+courses.length)
console.log("Course after pop "+courses.length)
* The pop() : This function removes last item from the Tuples * The push() : This function insert new item in the Tuples The output of the above code is as follows −
Editing Tuples Tuples values can be changed that means you can update or change the values of tuple elements.
Example
var courses= ['Java',"C++","C","typeScript"];
console.log("Tuple value at index 0 "+courses[0])
//Update here with new value
courses[0] = ‘ASP.NET’
console.log("Tuple value at index 0 changed to "+courses[0])
And the output will be :
Destructuring a Tuple You have already seen array destruct. Same like array, we can also break up Tuples into parts. And display as an individual entity.
Example
var nums =[100,200]
var [x,y] = nums
console.log( x )
console.log( y )
Its output is as follows −
