removing unused vars and throwing the errors

                   
|Q            |A  |
|---          |---|
|Bug Fix?     |n  |
|New Feature? |n  |
|BC Breaks?   |n  |
|Deprecations?|n  |
|Tests Pass?  |n  |
|Fixed Tickets|   |
|License      |MIT|
|Doc PR       |   |
                   


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Hm, I must have had a reason for doing this in this way? It is possible that I was wanting to expose `$error` from the builder? Otherwise I could have just thrown the error instead of keeping it around...