😵‍💫 Better messages for errors from explicator

[favonia]

Currently the errors from the Explicator cannot be understood by normal human beings. Some ideas:

1. Register a printer for these exceptions and dumy the range (but what if the string source is huge).
2. Provide an opt-in slow but thorough check for all positions before the explication.

[favonia]

Actually, maybe we should automatically check every range when there's any error at all from the explicator. 🤔