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Diffstat (limited to 'tools/addon-sdk-1.7/packages/api-utils/docs/environment.md')
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diff --git a/tools/addon-sdk-1.7/packages/api-utils/docs/environment.md b/tools/addon-sdk-1.7/packages/api-utils/docs/environment.md new file mode 100644 index 0000000..b5057a2 --- /dev/null +++ b/tools/addon-sdk-1.7/packages/api-utils/docs/environment.md @@ -0,0 +1,43 @@ +<!-- This Source Code Form is subject to the terms of the Mozilla Public + - License, v. 2.0. If a copy of the MPL was not distributed with this + - file, You can obtain one at http://mozilla.org/MPL/2.0/. --> + +Module provides API to access, set and unset environment variables via exported +`env` object. + + var { env } = require('api-utils/environment'); + +You can get the value of an environment variable, by accessing property that +has name of desired variable: + + var PATH = env.PATH; + +You can check existence of an environment variable by checking if property with +such variable name exists: + + console.log('PATH' in env); // true + console.log('FOO' in env); // false + +You can set value of an environment variable by setting a property: + + env.FOO = 'foo'; + env.PATH += ':/my/path/' + +You can unset environment variable by deleting a 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 |