Mathics3
Revise escape sequence scanning
Refactor the scanner. Remove prescanner. Handling escape sequences is not a separate phase, but instead is integrated into the scanning phase.
@mmatera There is still a lot to do regarding writing tests and ensuring we handle errors and everything correctly.
But since this is getting large, this is a heads-up as to what's on the horizon.
@mmatera merging needs to be coordinated with https://github.com/Mathics3/mathics-core/pull/1403 since exception handling has been revised. (In a previous PR, you commented on the use of TranslateErrorNew.)
After this PR, we'll still need to handle boxing expressions inside strings. Boxing expression outside strings, I think, works. But I haven't been able to get to galatea to understand what is expected versus not.