How to Declare Constants in JavaScript?
ES6 provides a new way of declaring a constant by using the const keyword which creates a read-only reference to a value:
const CONSTANT_VALUE = "someValue" ;
This works in almost all browsers.
Capitalization indicates that some values should be constant.
Local variables with block scope can be declared with const. Assuming, we have a constant variable CONSTANT_VALUE . After declaring a value like a constant variable, you can’t assign a new value to it:
Javascript const keyword
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Javascript const keyword
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Javascript const keyword
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The constant cannot change through re-assignment
constant cannot be re-declared. Const can be changed if it is an object because when you're adding to an array or object you're not re-assigning or re-declaring the constant, it's already declared and assigned, you're just adding to the "list" that the constant points to.
So this works fine:
Javascript const keyword for objects
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Javascript const keyword for array
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ES2015 introduced two new JavaScript keywords: let and const . Variables defined with const behave like let variables, except they cannot be re-assigned. In the programming world, a constant is something that does not change. The const creates a constant that is a read-only reference to a value, which does not mean the value it holds is immutable. It only indicates that the variable identifier cannot be re-assigned.