Avoid using dot notation with objects and instead use `const` for declaring variables for more

interface obj {
  bar: string
}

function randomFunction() {
  let foo: obj = { bar: "" }
  foo.bar = "hip"
}

let snack: obj = { bar: "" }
snack.bar = "hop"

Upon transcompiling, a warning from tslint pops up:

Identifier 'foo' is never reassigned; use 'const' instead of 'let'. (prefer-const)

Interestingly, the same warning does not occur with the variable snack.

To suppress this warning in the console output, I can use

/* tslint:disable: prefer-const */

I have not come across any reported bugs on the tslint project. As a newcomer to typescript, I'm left wondering if I am making a mistake here.

Answer №1

When using tslint, it suggests changing let to const because the variable foo is not being reassigned.

To fix this error, simply use const instead:

const foo: obj = { bar: "" };
foo.bar = "hip";

Keep in mind that using const only prevents reassigning the variable itself:

 const foo = { bar: "" };
 foo = { bar: "" }; // results in an error

It does not make the object immutable.

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