Add command line option to treat batch files as individual lines in interactive mode

[benjaminselfridge]

This would add an additional flag for the -b FILE batch mode for cryptol, which would have the effect of reverting to the old behavior. That behavior includes both:

• using <interactive> as the file name in error messages
• not tracking line numbers in error messages (so any error is reported as occurring on "line 1", regardless of where it appeared in the file)

The reason I need this is to keep the error messages in Programming Cryptol consistent with what the actual error message output would be.

As an example, suppose we have a file in.cry containing the following:

  True
  false
  False : Bit
  if True && False then 0x3 else 0x4
  False || True
  (True && False) ^ True
  ~False
  ~(False || True)

When I run cryptol -b in.cry, I get the following output:

True
[error] at in.icry:2:1--2:6 Value not in scope: false
False
0x4
True
True
True
False

I'd like this flag to have the effect of changing the above output to:

True
[error] at <interactive>:1:1--1:6 Value not in scope: false
False
0x4
True
True
True
False

[robdockins]

What if we add a separate --interactive-batch = <FILE> option instead of having another option that changes the semantics of -b? I don't think it makes much difference, but is maybe a little bit cleaner.

[benjaminselfridge]

Yeah, I like that better.