Generic Classes

How many classes does it take to store a number, a string and a user in the same way? With only the tools from the earlier chapters, the answer is three, and each one repeats the same code. A generic class reduces that to one class that takes a type parameter, in the same way a generic function does.

One Class for Each Type

Here is a small class that holds one number and lets you read or replace it:

class NumberStore {
  private value: number;

  constructor(value: number) {
    this.value = value;
  }

  getValue(): number {
    return this.value;
  }