safe-proxy

safe-proxy is a Javascript utility to allow for safe accessing of nested properties by soaking up nulls, inspired by Coffeescript's existential operator. It is the spiritual successor to safe-access. My friend Palash had the genius idea of improving safe-access’s syntax for calling functions by using ES6 Proxies. Note that since the ES6 Proxy spec is still in flux (no browsers have implemented the latest spec as of January 2015), this is not meant to be used in production. However, it’s really freakin’ cool, so try it out.

Install

npm install safe-proxy

Usage

Usage of ES6 Proxies is hidden behind a flag in io.js, so in order to use them, you will need to run your application with the --harmony-proxies flag.

Use safe-proxy like this:

var safe = require('safe-proxy');
safe(obj).that.is.very.nested.__value;
// the same as `obj.that.is.very.nested` EXCEPT
// returns undefined if any property in the chain is undefined

You can access arrays and call functions as you normally would. Just remember to access __value at the end.

safe(obj).nested.property.and.array[0].func('some', 'args').__value;

What's going on?

You can think of calling safe(obj) as wrapping obj in an object which will not throw an error no matter what properties you access or functions you call on it (even if obj is undefined, for instance). In order to unwrap the value, you’ll need to access the special property __value.

Development

Install io.js, clone this repo, and then from directory root run npm install. Start running tests with npm test. Tests will re-run when files change.

License

safe-proxy is freely distributable under the terms of the MIT license.