Use tail-recursive functions instead of foldl
We love high-order functions!
Using
'andalso','orelse', and the like, might save a 'case' or two
They're not intended to be used that way and the resulting code messes up with dialyzer
Replace
lists:mapwith eitherlists:foreachor list comprehensions
There is not true that LCs are better than list:map in all scenarios.