Allow try/catch statements to be nested

[molovo]

This may or may not be possible. The try command needs to launch a subprocess to allow the exception to be caught, which means that modifying the global environment is not possible. To allow statements to be nested we'd need to maintain an 'exception stack' in an array, but cannot do this in its current form due to the use of a subprocess. Thrown exceptions are currently reported back to the global process by echoing the exception and message, so we could maintain the stack outside of the try block, but my first attempt at this didn't work. Something to look into.

[daCyberpunk]

not really true.
You can use named pipes for it. If I understand your prob right.
This way command is not running in a subprocess.

PIPE=$(mktemp -u)
mkfifo $PIPE
# attach it to file descriptor 3
exec {hlpr}<>$PIPE
# unlink the named pipe
rm $PIPE
command >&$hlpr
echo -ne $'\0' >&$hlpr
read -d$'\0' -u $hlpr output;
# close fd
exec {hlpr}>&-