Took some code from Deno and packaged them so you don't have to copy paste them

Should map errors correctly. See more in this issue.

lib.rs:

There are many types of errors in Deno:

• AnyError: a generic wrapper that can encapsulate any type of error.
• JsError: a container for the error message and stack trace for exceptions thrown in JavaScript code. We use this to pretty-print stack traces.
• Diagnostic: these are errors that originate in TypeScript's compiler. They're similar to JsError, in that they have line numbers. But Diagnostics are compile-time type errors, whereas JsErrors are runtime exceptions.