Constant Declaration Keyword, const
const is short for Constant, which means that once a value has been set, it cannot be changed.
Therefore, a variable declared using const cannot have its value altered once it is assigned.
const birthYear = 1995;
In the example above, the constant birthYear is assigned the numeric value 1995.
Since birthYear is declared with const, its value cannot be changed once set.
The scope of a const declared variable, like let, is block-level scope.
Thus, a variable declared with const inside curly braces is not accessible outside that code block.
Why Use const as a Constant Variable?
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To Store Values That Should Not Change: It is used when you want to safely store values that should not change once set, such as a website's default color or a user's birth year.
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Improving Code Stability: By using
const, you prevent the value from being accidentally modified. This helps to reduce errors in your program, making it more robust.
A constant declared with const can have its value changed.
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