for the third:
/\+\+[a-zA-Z_]+[0-9a-zA-Z_]*/{
x/\+\+/d
a/++/
}

the braces stuff is pretty tough, but maybe someone will have an idea.
however it is really easy to do it by hand in acme.

click on the inside of the opening paren with a double click then click button 2
(while still holding down button 1 from the double click) this will cut everything
inside that and the matching paren. then highlight the remaining () and while 
still holding down button 1 push button3.
Looks complicated written down but it's a really quick and easy to learn sequence.



2013/1/11 Peter A. Cejchan <tyapca7@gmail.com>
## How to do this with [acme | sam | sed ]  ?
# compound commands
# remove outermost pair of braces:  abcd(x+(y-z))efgh  --> abcdx+(y-z)efgh
         [ no idea :-( ]
# remove semicolon before // comments:  xyz;[tab][space]*//  --> xyz
         [ Edit /;[     ]*\/\// Edit s/;//      # find and remove semicolon
before // comments ]
# prefix to postfix operator: ++i --> i++
         [ Edit s/\+\+[a-zA-Z]+[0-9a-zA-Z]*/&++/ Edit s/\+\+/d]

thanks,
++pac