[Cuis] Overriding the text styler

[Phil (list)]

I've been looking at what it would take to add syntax
highlighting/coloring for <package I've already spent too much time
talking about> and think I have a better understanding of what's
involved.  

Basically, there needs to be a level of indirection added similar in
concept to compilerClass.  However, since the Squeak doesn't appear to
have been designed with a modular text styler in mind it's not going to
be as nice and neat (at least not right away.)  InnerTextMorph appears
to be where the styling actually occurs and it in turn depends on
SHTextStylerST80 to do the work which is directly hard-coded in 5 places
in the image.  At the very least there would need to be a global setting
that can be overridden which would default to SHTextStylerST80.  This
could be done via a class method (on Object or somewhere else in the
hierarchy?) or probably better would be a preference setting that would
define the default styler.  From there, there would need to be one of
the following:

1) A per-text object being styled check to determine what styler to use
(i.e. in the code browser there would need to be a check of what class
you're styling for, and for other standalone text morphs you'd need to
override as needed)

2) Anyone wanting to customize styling would need to completely take
over styling everywhere and deal with use cases like mine dynamically in
their custom styler internally.

While I'll take any accommodations I can get for my needs, I'm thinking
it would be pretty cool to have more modular styler setup in the various
code browsers.  In a Smalltalk-only world it would allow you to play
around with changes to the styler in a safer manner (i.e. if you could
have it only apply to a specific class hierarchy, your other browser
windows would continue to work properly while you're writing/debugging
it).  But it could also be handy if at some point we wanted to support
something fancy like StyledTextEditor or Markdown for package/class
comments.  And of course there's my use case where your OMeta/Lisp/DSL
code could be nicely styled as a first-class citizen just like Smalltalk
code in the browser... but also in workspaces (i.e. you could have
multiple DSL-specific, styled workspaces providing live interaction...
how cool would that be?)

Seems like a nice feature to have... what do you think?  If this is
agreeable, I'm fine doing the work on the first cut at this.  I just
need to know how I should handle the top level indirection and whether I
should be going for an all-or-nothing monolithic approach (i.e. global
replacement of the styler for everything) or keeping a modular approach
in mind at the cost of a bit more complexity?

Thanks,
Phil