To be honest I have never found any functional language that gives anything near helpful error messages. I have found that the best way is not to read the error

To be honest I have never found any functional language that gives anything near helpful error messages. I have found that the best way is not to read the error messages but to pattern match on the phrases. Sounds like a downside but the benefit is it takes only a mere fraction of a second to look at an error message and guess what is wrong once you get comfortable. There are not too many patterns either.