Question: I've tried, with M-x align-regexp:

```
<-|=
(<-|=)
\(<-|=\)
\\(<-|=\\)

```

And the ones with <- and = reversed. But none work?

Example code as follows:

```
  (flags, params, errs) <- parseArgs <$> getArgs
  let options = foldr id [] flags -- Apply functions to list

```

Answer: 
try `\(<-\|=\)` -- you need the (backslashed) parentheses, **and** you need to backslash the `|`
You need to escape the `|`:

```
\(<-\|=\)

```