Contenido del Curso
Introduction to JavaScript (staging)
Introduction to JavaScript (staging)
Constant 2/3
Block Scope of Constants
Declaring a variable with the const
keyword is similar to declaring a variable with the let
keyword when it comes to Block Scope, for example.
The personName
declared in the block, in this example, is not the same as the personName
declared outside the block:
const personName = "Mike"; if (2 > 1){ const personName = "Smith"; } console.log(personName)
We gave you a good understanding of block-scope but it is not a good practice to use the same name inside and outside the code block.
Constants are Assigned Values at the time of Declaration
In JavaScript, we can initialize variables in one line and assign them values in the next line with the let
and the var
keywords but we cannot do that with the const
keyword, and if we do so, we get an error, for example.
let age; age = 23; console.log(age) var height; height = 5; console.log(height);
But with const
we get an error.
const PI; PI = 3.14159265359; console.log(PI);
Swipe to show code editor
A constant variable named gravity
has been given to you. But it cannot be displayed due to some error. Your task is to make changes in the code so that it can be displayed properly.
¡Gracias por tus comentarios!
Constant 2/3
Block Scope of Constants
Declaring a variable with the const
keyword is similar to declaring a variable with the let
keyword when it comes to Block Scope, for example.
The personName
declared in the block, in this example, is not the same as the personName
declared outside the block:
const personName = "Mike"; if (2 > 1){ const personName = "Smith"; } console.log(personName)
We gave you a good understanding of block-scope but it is not a good practice to use the same name inside and outside the code block.
Constants are Assigned Values at the time of Declaration
In JavaScript, we can initialize variables in one line and assign them values in the next line with the let
and the var
keywords but we cannot do that with the const
keyword, and if we do so, we get an error, for example.
let age; age = 23; console.log(age) var height; height = 5; console.log(height);
But with const
we get an error.
const PI; PI = 3.14159265359; console.log(PI);
Swipe to show code editor
A constant variable named gravity
has been given to you. But it cannot be displayed due to some error. Your task is to make changes in the code so that it can be displayed properly.
¡Gracias por tus comentarios!