Using Type Guards in Redux Middleware

Demonstrates how to implement a type guard to differentiate between known action types within Redux middleware for proper type casting.

function isSpecificAction(action) {
  return action && action.type === 'SPECIFIC_ACTION_TYPE';
}

Defines a user-defined type guard to check if an action is of type 'SPECIFIC_ACTION_TYPE'.

const myMiddleware = store => next => action => {
  if (isSpecificAction(action)) {
    // Now TypeScript understands that 'action' is of the 'SpecificAction' type.
    // Additional logic for 'SpecificAction' can now be safely added here.
    console.log(`Processing ${action.type}`);
  }
  return next(action);
};

Implements Redux middleware using the type guard to handle actions of a specific type, passing other actions through to the next middleware.