2021年2月18日(木) 0:56 Robert Elz <k...@munnari.oz.au>: > For a long time [...] > > [...] And it all has to be recursive, > as $() cmdsubs can occur in the middle of words in the middle of other > cndsubs.
Thank you for the historical story. > Chet can explain more if he feels it is warranted, but I believe that even > today, bash uses a very heuristic type of almost pretend to be a parser > to deal with these things Yes, that is done in `parse_comsub' in `parse.y' which I mentioned in some earlier reply in this tree. > None of the (current anyway) problems represent code that anyone trying > to solve a real problem (as distinct from stressing the parser) would > ever write, so one can understand a certain reluctance to spending a lot > of time fixing things that only even happen in stress tests. I actually doubt that it takes so much time to fix them... Have you ever written a shell parser? Some time ago I have written a simple shell parser mimicking the Bash behavior without thinking the details, but it correctly parses all the command substitutions reported here.
