This is a brief example of how to pass command-line arguments to a "headless" Elm program running under Node.js.
After cloning this repo, you'll need to install the Elm core package in this directory:
elm package install
Then compile Main.elm to produce main.js:
elm make --output main.js Main.elm
Finally run the example with some example arguments:
node js.js param1 param2 arg3
There's also an HTML file to play with, to get a sense of the more conventional use of ports. You can interact with this example directly from the Javascript console in your browser. Try commands like this:
worker.ports.stdin.send(["var1", "var2"])
Let me know what's good or bad about this example. I'm also interested in paring out any parts that aren't necessary to this demonstration.
In this example I'm only reading one line from stdin and writing only a couple of lines to stdout. However, it should be possible to extend this to cover the most common features of a standard Unix filter.