Safe Touch

Retrieving deeply buried properties is a common problem in JavaScript, it could crash your application if you try to access a property that doesn't exist.

const state = { user: { name: "EnixCoda" } };
console.log(state.user.name); // 'EnixCoda'
state.user = null;            // simulating logout
console.log(state.user.name); // Uncaught TypeError: Cannot read property 'name' of null

Safe touch is a safe way to access deeply buried properties.

const $state = safeTouch(state);      // retrieving properties from $state is always safe
console.log($state() === state);      // true; invoke to get the original value
{
  let { user: { name } } = $state;    // support native destructuring
  console.log(name());                // 'EnixCoda'
  console.log($state.user.name());    // 'EnixCoda'
}

Object.assign(state, { user: null })  // simulating logout
{
  let { user: { name } } = $state;    // support native destructuring
  console.log(name());                // undefined; no errors!
  console.log($state.user.name());    // undefined; no errors!
}

Playground

Available as safe-touch on npm.

> yarn add safe-touch

Why choose Safe Touch?

• state && state.user && state.user.name is verbose.
• wrapping with try ... catch is verbose and creates new code block.
• lodash _.get has no TypeScript support.