write: (name: string) -> Promise<mixed>

[krainboltgreene]

Promises are a great form of handling concurrency where a single value is passed around. Instead of doing a callback, now users can chain then's or catch's.

[ncuillery]

Hey I'd love to see Promise support for the write method.

I'm not a maintainer, but I review the code and I think the Promise support would better be optional:

• If a callback is provided, the write method works just like before (no breaking change)
• It no callback is provided, the writemethod returns a Promise

Lots of libraries works like that.

[krainboltgreene]

The only failing bit is node 0.10, which frankly...it's way past lts.

[addisonElliott]

Came across this same problem and I agree with @ncuillery with the logic implementation. Quite a few libraries do handle it like that and it's intuitive to most users.

In the meantime until this PR is accepted, an applicable solution is to promisify the function and save it in gm, like so. Just add it to the top of your code before running any code using gm. Just use the writePromise function and it will return a promise instead.

gm.prototype.writePromise = util.promisify(gm.prototype.write);