SteelToe - object, do not shoot me in the leg!

SteelToe is a small javascript snippet designed to solve the problem of accessing the undefined properties of an object. This is especially important when accessing nested properties. It also implements the possibility of auto-authentication, which simplifies the creation of the desired properties in order. In general, a rather healthy sugar in OOP.

Getting Values

First way

var object = { info: { name: { first: 'Jonathan', last: 'Clem' } } }
steelToe(object)('info')('name')('last')();           // 'Clem'
steelToe(object)('info')('features')('hairColor')();  // undefined

Second way

var object = { info: { name: { first: 'Jonathan', last: 'Clem' } } }
steelToe(object).walk('info.name.last');          // 'Clem'
steelToe(object).walk('info.features.hairColor'); // undefined

Definition of Values

var jonathan = { info: { name: { first: 'Jonathan', last: 'Clem' } } },
steelToe(jonathan).set('info.name.middle', 'Tyler');
steelToe(jonathan).set('info.favorites.movie', 'Harold & Maude');
jonathan.info.name.middle; // Tyler
jonathan.info.favorites.movie; // Harold & Maude

What is going on here

Imagine - you have a complex Javascript object, with a large nesting of properties, which, for example, you got from JSON. And, for example, you need to do something like this:

var fatherFirstNames = [];
for (var i = 0; i < families.length; i ++) {
  var first = families[i].father.info.name.first;
  if (first) {
    fatherFirstNames.push(first);
  }
}
// TypeError: 'undefined' is not an object (evaluating 'family.father.info.name.first')

- Bliiin !, you say - a stupid shot in the leg! You can easily fall out an error TypeError, because nothing guarantees that a property is fatherdefined or that it has the properties you require. Usually, to prevent errors of this kind, we write wretchedness, such as this

var farherFirstNames = [];
for (var i = 0; i < families.length; i++) {
  var father = families[i].father;
  if (father && father.info && father.info.name && father.info.name.first) {
    fatherFirstNames.push(father.info.name.first);
  }
}

Bueee ... See how elegantly SteelToe solves this problem!

var fatherFirstNames = [];
for (var i = 0; i < families.length; i++) {
  var name = steelToe(families[i]).walk('father.info.name.first');
  if (name) {
    fatherFirstNames.push(name);
  }
}
fatherFirstNames; // ["Hank", "Dale", "Bill"]

No more TypeError! Happiness!

The library is presented on the site , and on github .