Hello,

I would like to scratch a long-standing itch and introduce the "c"
macro, which is basically a way to handle multiple counters in an Org
document. So, the following document

  * Part {{{c}}}
  * Part {{{c}}}
  * Part {{{c(other)}}}
  * Part {{{c}}}
  * Part {{{c(other)}}}

is expanded as

  * Part 1
  * Part 2
  * Part 1
  * Part 3
  * Part 2

Initially, I wanted to name it "#", but macro names must start with
[a-zA-Z]. I also wanted something short, hence the "c". It could also be
"n". Feel free to suggest something better.

Anyway, I attach an implementation for the feature along with
a documentation update. If the feature is to be included in Org, I'll
also write tests and an ORG-NEWS entry.

Feedback welcome.

Regards,

-- 
Nicolas Goaziou                                                0x80A93738