How do you work with variables outsite of the try catch but changing its value inside?

[felipegutierrez]

Hi,

I have some function that change some variable inside the try/catch and return 0 or 1.

My first problem is when I return 0 or 1 it throws an error.

My second problem is: I placed the return 0 or 1 outside of the try/catch, but I change some variable inside the try/catch. And then I cannot see the new value of this variable.

Kind Regards,
Felipe

[niieani]

Please provide some example code. Hard to reason about this without any examples :)

[felipegutierrez]

cat testTry.sh 
#!/usr/bin/env bash
source "$( cd "${BASH_SOURCE[0]%/*}" && pwd )/lib/oo-bootstrap.sh"

# load the type system
import util/log util/exception util/tryCatch util/namedParameters

# load the standard library for basic types and type the system
import util/class


VALUE="0"
echo "before try: "$VALUE
try {
	echo "inside try: "$VALUE
	VALUE="1"
	echo "inside try: "$VALUE
} catch {
        echo "Caught Exception:$(UI.Color.Red) $__BACKTRACE_COMMAND__ $(UI.Color.Default)"
        echo "File: $__BACKTRACE_SOURCE__, Line: $__BACKTRACE_LINE__"
        Exception::PrintException "${__EXCEPTION__[@]}"
}
echo "after try: "$VALUE

When I execute I cannot work with the variable after try/catch

# ./testTry.sh 
before try: 0
inside try: 0
inside try: 1
after try: 0

[niieani]

Unfortunately, a try/catch block creates a subshell. In bash it's currently impossible to affect the parent shell from a subshells, so the only workaround I can think of would be to capture the try/catch stdout in a variable.

[rbukovansky]

Or you can save result to file and update variable after try/catch is done...

I personally use:

try {
  commandToTry > ${HOME}/.result_of_command 2>&1
} catch {
  rm -f ${HOME}/.result_of_command
  # handle error
}
results=$(<${HOME}/.result_of_command)
rm -f ${HOME}/.result_of_command