ljharb
make-generator-function 
Returns an arbitrary generator function, or undefined if generator syntax is unsupported. If both generator syntax and concise method syntax are supported, the generator function returned will have a "concise" property containing a concise generator method.
Example
var maybeGeneratorFunction = require('make-generator-function');
if (maybeGeneratorFunction) {
assert(typeof maybeGeneratorFunction === 'function');
var maybeConciseGeneratorMethod = maybeGeneratorFunction.concise;
if (maybeConciseGeneratorMethod) {
assert(typeof maybeConciseGeneratorMethod === 'function');
}
} else {
assert(typeof maybeGeneratorFunction === 'undefined');
}Tests
Simply clone the repo, npm install, and run npm test