So, we've been actually discussing this on github and maybe others can participate over there, check
https://github.com/pure-data/pure-data/issues/505
or... maybe we can use this thread instead... :) seems like github discussions are always more limited.
The thing in the way now is wether "{" and "}" should be officially incorporated with a new syntax, like nested lists. There are arguments against as in the last message by christof here and I agree and think we could just let "{" and "}" be supported as regular characters and that we can expand the usage of dollar signs for expanding Pd's syntax, like ${ and $}
And, also, I'd like to point that there are forks of Pd that actually already allow "{" and "}"... I can see why one would disregard this, but it's something worth noting. You can already do this in PlugData and PurrData/Pd-L2ork, and the patches actually work and are already compatible to Pd Vanilla.
I also don't see an expansion of the language syntax coming up very soon or easily, so just allowing "{" and "}" could be good to at least get this issue out of the way, since it's been bugging people for edge cases for ages.
What do you people say?
cheers