index.js
function set(key, val) {
    return process.env[key] = (process.env[key] === undefined ? val : process.env[key]);
}
function set(key, val) {
    return process.env[key] = (process.env[key] === undefined ? val : process.env[key]);
}
function set ( key , val ) { return process . env [ key ] = ( process . env [ key ] === undefined ? val : process . env [ key ] ) ; }
sets environment variable if it does not exist already env variables are stringified when set
sets environment variable if it does not exist already env variables are stringified when set