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Discussion on: Pure Functions with Typescript

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havespacesuit profile image
Eric Sundquist

const in TypeScript doesn't work how you show it. You are able to update the properties of an object or array declared with const. You just cannot reassign the variable to a new object.

So I can do

const product: Product = {
  title: "Awesome Car",
  quantity: 32,
  price: 2990
};

product.title = "Awesome Camera"

while I cannot do

const product: Product = {
  title: "Awesome Car",
  quantity: 32,
  price: 2990
};

product = {
  title: "Awesome Camera",
  quantity: 32,
  price: 2990
};
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aminejvm profile image
Amine

Hey sorry I forgot to add as const in the example thank you for noticing it.

const product: Product = {
  title: "Awesome Car",
  quantity: 32,
  price: 2990
} as const ;

product.title = "Awesome Camera"

after adding const assertion we can't edit the title property. Thank you for your feedback ))