gistfile1.txt

Broken links 1 http://code.google.com/p/google-code-prettify/
             2 http://google-code-prettify.googlecode.com/svn/trunk/README.html
             3 https://code.google.com/archive/p/google-code-prettify/source#svn%2Ftrunk%2Fsrc

We're changing the way syntax highlighting is done on the Stack Exchange engine.

As you probably know, we use [Google Code Prettify][1] for automatic syntax highlighting.

Since the beginning, we've had kind of a boolean setting **per website**:

1. code blocks are *always* automatically highlighted (Stack Overflow, programmers.se, etc)
2. code blocks are *never* highlighted (Super User, photo.se, bicycles.se, etc)

We are now moving to a **more tag-based syntax highlighting** method. There are one of three possible syntax highlighting hints associated with each tag:

1. *specific* language hint -- tell prettify to use that language
2. *default* language hint -- let prettify infer a language
3. *null* -- no hint, no syntax highlighting

(all specific languages must be in the [set that prettify supports][2], obviously)

> bsh, c, cc, cpp, cs, csh, cyc, cv, htm, html,
  java, js, m, mxml, perl, pl, pm, py, rb, sh,
  xhtml, xml, xsl.

[extensions available][3] are

> apollo, css, go, hs, lisp, lua, ml, proto, scala, sql, vb, vhdl, wiki, yaml

Thus:

- If a question has no tags with a default or specific language hint, *no* syntax highlighting will be performed.

- If a question has at most one tag with a specific language hint, plus any number of default or null hints, then syntax highlighting will be performed only for that *specific* language.

- If a question has two tags that both define specific languages, it uses *default* and lets prettify infer as it always has.

- As long as a question has one or more tags with default language hints, but none with a specific language hint, it uses *default* and let prettify infer as it always has.

The default tag syntax highlighting hint is *null*. So the question is, **which tags should have the *default* and *specific language* hints?** I put my initial pass through the first 6 pages of tags here:

http://pastebin.com/AWMtu5rK

If you feel there should be changes, post your diffs as answers.

(and yes, there are plans to allow [an explicit override syntax][4] but for now we want to try to get the defaults mostly correct before worrying about the edge conditions)

[1]: https://github.com/google/code-prettify
[2]: https://github.com/google/code-prettify/blob/master/README.md
[3]: https://github.com/google/code-prettify/tree/master/src
[4]: https://meta.stackexchange.com/questions/63800/interface-options-for-specifying-language-prettify