assignment to constant variable

The error "assignment to constant variable" occurs when you try to change the value of a variable that has been declared as a constant. In most programming languages, constants are declared using the keyword "const" or a similar syntax. Once a constant is assigned a value, it cannot be changed throughout the program execution.

For example, in JavaScript, you might encounter this error if you try to reassign a value to a constant variable:

const PI = 3.14;
PI = 3.14159; // Error: Assignment to constant variable

To fix this error, you should either declare the variable as mutable (using `let` or `var`, depending on the language), or avoid reassigning values to constants.