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##  #   ##      ##      ## ##    # #    #    # #   ##
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$ curl repovive.com/roadmaps/javascript/introduction-to-typescript/union-types

░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░██████████████████████████████████████████████████████████████████████████████

#####   ######  #####    ###    #   #  ###  #   #  ######
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#####   ####    #####   #   #   #   #   #   #   #  ####
##  #   ##      ##      ## ##    # #    #    # #   ##
##   #  ######  ##       ###      #    ###    #    ######

$ curl repovive.com/roadmaps/javascript/introduction-to-typescript/union-types

Repovive

Union Types - Introduction to TypeScript | JavaScript | Repovive

Repovive.

JavaScript22 sections · 783 units18h total

Open in Course

Union Types

Accept multiple types

Union types allow a value to be one of several types:

let id: string | number;
id = "abc"; // OK
id = 123;   // OK
id = true;  // Error

function format(value: string | number) {
  if (typeof value === "string") {
    return value.toUpperCase();
  }
  return value.toFixed(2);
}