Stable
Access, set and clear environment variables.
Usage
var { env } = require('sdk/system/environment');
You can get the value of an environment variable, by accessing the property with the name of the desired variable:
var PATH = env.PATH;
You can check for the existence of an environment variable by checking whether a property with that variable name exists:
console.log('PATH' in env); // true console.log('FOO' in env); // false
You can set the value of an environment variable by setting the property:
env.FOO = 'foo'; env.PATH += ':/my/path/'
You can unset an environment variable by deleting the property:
delete env.FOO;
Limitations
There is no way to enumerate existing environment variables, also env
won't have any enumerable properties:
console.log(Object.keys(env)); // []
Environment variable will be unset, show up as non-existing if it's set to null
, undefined
or ''
.
env.FOO = null; console.log('FOO' in env); // false env.BAR = ''; console.log(env.BAR); // undefined