Ikiwiki's preprocessor parser cannot deal with arbitrary nested preprocesor directives. It's possible to nest a directive with single quoted values inside a triple-quoted value of a directive, but that's all.
It's not possible to unambiguously parse nested quotes, so to support nesting, a new syntax would be needed. Maybe something xml-like?
You can, however, unambiguously parse nested square brackets, and I think that would solve the problem, as long as you never allow the contents of a directive to contain a partial directive, which seems reasonable to me.
For example, I think you can unambiguously parse the following:
[[!if test="enabled(template) and templates/foo" then=""" [[!template id=foo content="""Flying Purple People Eater"""]] """]]
Yes it's definitely possible to do something like that. I'm not 100% sure if it can be done in perl regexp or needs a real recursive descent parser though.
In the meantime, this is an interesting approach: https://github.com/timo/ikiwiki/commit/410bbaf141036164f92009599ae12790b1530886 (the link has since been fixed twice)
[[!directive text=<<FOO ... FOO]]
Since that's implemented, I will probably just merge it, once I satisfy myself it doesn't blow up in any edge cases. (It also adds triple single quotes as a third, distinct type of quotes, which feels a bit redundant given the here docs.) --Joey
Hmm, that patch changes a
m///msgx. Meaning that any '^' or '$' inside the regexp will change behavior from matching the start/end of string to matching the start/end of individual lines within the string. And there is one legacy '$' which must then change behavior; the "delimiter to next param".
So, I'm not sure what behavior that will cause, but I suspect it will be a bug. Unless the `\s+|$' already stops matching at a newline within the string like it's whitespace. That needs more alalysis. Update: seems it does, I'm fairly satisfied that is not a bug.
Also, the patch seems incomplete, only patching the first regexp but not the other two in the same function, which also are quoting-aware. --Joey
Yes, I'm terribly sorry. I actually did edit the other two regexps, but I apparently missed copying it over as well. Should have been doing this in a git repo all along. Look at the new commit I put atop it that has the rest as well: (redacted: is now part of the commit linked to from above) Also: I'm not sure any more, why I added the m modifier. It was very late at night and I was getting a bit desperate (turned out, the next morning, I put my extra regexes after the "unquoted value" one. heh.) So, feel free to fix that. --Timo
I've fixed the patch by rebasing, fixed the link above. I'm still not sure if the m modifier for the regex is still needed (apparently I didn't put it in the other regexes. Not completely sure about the implications.) Am now trying to wrap my head around a test case to test the new formats for a bit. --Timo