Modernise

[lokedhs]

Modernise the code style (in particular, remove old style declarations). Remove TERMCAP support Map the ITS character set to Unicode. This is enabled when the user has a UTF-8-based locale, but it can be manually enabled using the -u flag, or disabled using -U.

[larsbrinkhoff]

I'm unsure about _ and ^. Maybe they should be left with their ASCII definition.

I'm also unsure about |, }, and ~. It looks like they were different in SAIL, but that they retain their ASCII graphics in ITS.

[larsbrinkhoff]

I'd like some pull request hygiene to be applied before the final result is merged:

• Rebase on top of current master
• Merge related changes into one commit
• Split unrelated changes into several commits

This makes for easier reviewing now, and maintenance in the future.

[larsbrinkhoff]

I tested printing codes 007-015 in ASCII and image modes. Plus 001 and 016 for reference.

Image mode:

A↓ G  Iγ J
 N∞       K↑ L± M

ASCII mode:

A↓ G  I  J
           K↑ L± M
 N∞

As you can see, they're very close. Only 013 and 014 print their graphical character in both modes. 011 does so only in image mode. The rest of the characters do some control function. 015 only does carriage return in image mode, and CR+LF in ASCII mode.

So the question remains, how to print 007/π, 010/λ, 012/δ, and 015/⊕? EMACS does print all of those except 011/TAB, 012/↑J, and 015/↑M, but I supect that's by design.

I suspect I should try super image mode too.

[larsbrinkhoff]

Yep, super image mode does it:

A↓ Gπ Hλ Iγ Jδ K↑ L± M⊕ N∞