What is the method for retrieving properties from a generic in typescript?

In my code snippet, I am dealing with a generic type variable called data and I am looking for a way to access the values of its properties.

The method hasOwnProperty isn't effective in this case due to the generic nature of the data.

const data: T = getData();

for (const key in dato) {
  if (dato.prototype.hasOwnProperty.call(dato, key)) {
      const element = dato[key];
  }
}

Answer №1

When we talk about a generic type, we are referring to a type that is undefined or unknown. This means that we cannot determine its properties or if it even has any properties at all. Accessing these properties may be unsafe as we don't know what to expect. For example, an empty object {} could be considered a valid value for the data property.

In order to safely access properties of a generic type, we must specify or bind it to a type that contains those properties. This ensures that we can work with the type confidently without risking unexpected behavior.

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