Chris Keen zedd45

WTF Flow

[Flow][] static type checker is a wonderful attempt to bring [algebric data types][] to JS. It is still fairly new project and there for has few WTFs that can pull you down the rabbit hole. This document is attempt to document things that may seem like a WTF from the perspective of JS developer who tries to employ static type checker, or in other words, some items on the list may be very subjective & based on the background of the writer.

Polymorphic type that is a function

It is very likely that one will wind up using [Polymorphic functions][] to solve a more general problem. And if you define type alias for such a function you may be puzzled what is the right syntax should be used for such type definition.

Let's start with:

	function fish_prompt
	set_color blue
	echo -n [
	set_color cyan
	echo -n (whoami)
	set_color 3FF
	echo -n @
	set_color cyan
	echo -n (hostname\|cut -d . -f 1)
	set_color blue

	// give it a name so it reuses the same window
	var win = window.open(null, "redux-devtools", "menubar=no,location=no,resizable=yes,scrollbars=no,status=no");

	// reload in case it's reusing the same window with the old content
	win.location.reload();

	// wait a little bit for it to reload, then render
	setTimeout(function() {
	React.render(
	<DebugPanel top right bottom left >