[Lazarus] Regex and Syntax Highlighting

[Graeme Geldenhuys]

On 27 May 2010 02:33, Hans-Peter Diettrich wrote:
>
> Multi-line comments, or even worse: nested comments, require to pre-scan an
> file, before the highlighter can be used.

I don't think this is true. I briefly looked at the jEdit code that
manages the syntax highlighting, and it doesn't do multiple passes
over the file. It tokenizes a line, if that line contains something
that could span multiple lines (like  { or (* style comments), it
carries the state and context over to the next line. Then it processes
the next line etc... only a single pass seems to be used.

jEdit also supports code-folding, but I haven't looked at how they tie
that into the whole TextEdit component yet. The more I play with jEdit
the more impressed I get regarding all it's features and how
extensible it is via it's plugin system. A pretty amazing piece of
engineering in a very small download (2.5MB).

> undo-tracking, and foldable blocks come into play, and UTF-8 and tab
> expansion, then it may take longer to retrieve the text to show, the
> highlighter must be fault-tolerant to cover temporarily invalid tokens,

jEdit supports all that and more, and it is very fast! Like I said, a
very impressive piece of engineering.


-- 
Regards,
  - Graeme -


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