John Meacham
rather than start layout blocks right after the 'let' 'do' or 'where', put them on the next line with one more tabstop than the current line.
I've also a bit baffled by all the people apparently struggling with layout; I realize the rules are a bit complex, but it's something that "just works" for me. But then I also use this convention, (except in really simple cases: f x = let y = g x in h y f x = h y where y = g x (It could be because I use Emacs, though, where the hs mode has TAB cycling through the possible indentations.)
this makes your code independent of the tabstop and much easier to work with IMHO.
Also it is safer if you are using non-ASCII characters, e.g. f \x06de = case \x06de of foo -> bar blah -> -- where to align this? -kzm -- If I haven't seen further, it is by standing in the footprints of giants