DevYK 8466310f0c update README.md 3 سال پیش
..
.github 8466310f0c update README.md 3 سال پیش
lib 8466310f0c update README.md 3 سال پیش
.jscsrc 8466310f0c update README.md 3 سال پیش
.jshintrc 8466310f0c update README.md 3 سال پیش
.travis.yml 8466310f0c update README.md 3 سال پیش
LICENSE 8466310f0c update README.md 3 سال پیش
README.md 8466310f0c update README.md 3 سال پیش
example.js 8466310f0c update README.md 3 سال پیش
package.json 8466310f0c update README.md 3 سال پیش

README.md

undefsafe

Simple function for retrieving deep object properties without getting "Cannot read property 'X' of undefined"

Can also be used to safely set deep values.

Usage

var object = {
  a: {
    b: {
      c: 1,
      d: [1,2,3],
      e: 'remy'
    }
  }
};

console.log(undefsafe(object, 'a.b.e')); // "remy"
console.log(undefsafe(object, 'a.b.not.found')); // undefined

Demo: https://jsbin.com/eroqame/3/edit?js,console

Setting

var object = {
  a: {
    b: [1,2,3]
  }
};

// modified object
var res = undefsafe(object, 'a.b.0', 10);

console.log(object); // { a: { b: [10, 2, 3] } }
console.log(res); // 1 - previous value

Star rules in paths

As of 1.2.0, undefsafe supports a * in the path if you want to search all of the properties (or array elements) for a particular element.

The function will only return a single result, either the 3rd argument validation value, or the first positive match. For example, the following github data:

const githubData = {
        commits: [{
          modified: [
            "one",
            "two"
          ]
        }, /* ... */ ]
      };

// first modified file found in the first commit
console.log(undefsafe(githubData, 'commits.*.modified.0'));

// returns `two` or undefined if not found
console.log(undefsafe(githubData, 'commits.*.modified.*', 'two'));