Syntax highlighting in code elements

[jariji]

Some pages use <code class="language-python"> for syntax highlighting.

The HTML living standard says:

There is no formal way to indicate the language of computer code being marked up. Authors who wish to mark code elements with the language used, e.g. so that syntax highlighting scripts can use the right rules, can use the class attribute, e.g. by adding a class prefixed with "language-" to the element.

In my feeds, I see several classes being used for this purpose. Some specify the source language; others leave it implicit and use a library to guess.

count class                    example source
------------------------------------------------------------------------
  98  prettyprint              (Google Code Prettify)                                                                                                                                                                 
  77  sourceCode haskell       (Pandoc)                                                                                                                                                                                                                                                     
  75  highlight                (generic)                                                                                                      
  69  sourceCode               (Pandoc base)                                                                                                  
  52  language-python          (Jekyll)   

I would like to preserve syntax highlighting where possible. For the ones with specified language like class="language-python", that could be passed through or rewritten, and I could use prismjs to highlight it.

The ones with unspecified language, I'm not sure what's the best approach but I'd like to do something.

Related work: simplepie/simplepie#717 provides a rewriter: "The new rename_attributes() methods enables it. The id and class attributes could be renamed to data-sanitized-id / data-sanitized-class" which can then be highlighted.