Error in modifiying of const list

[sairaorgb]

Page URL

https://dart.dev/language/variables/

Page source

https://github.com/dart-lang/site-www/tree/main/src/content/language/variables.md

Describe the problem

var foo = const [];
foo = [1, 2, 3]; // Was const []
this was listed in the docs , but this is wrong right . we cant modify foo here

Expected fix

No response

Additional context

No response

I would like to fix this problem.

• I will try and fix this problem on dart.dev.

[thisissandipp]

We can, actually. The foo variable is declared using var, making it mutable. The value initially assigned to foo is a constant (an empty list) but can be reassigned because the variable itself is not marked as const or final.

Here is an equivalent code for the above example

const arr = [];
var foo = arr;

foo = [1, 2, 3];  // CAN DO THIS!
arr = [3, 4, 5];  // ERROR - CAN NOT DO THIS!

In this case, arr is a constant and cannot be modified, but foo is a regular variable and can be reassigned to a different list without any issue.