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I'm not sure if this has been answered, I've looked and haven't found anything that looks like what I'm trying to do. I also posted this to stackexchange (https://unix.stackexchange.com/questions/189293/create-array-in-bash-with-variables-as-array-name)

I have a number of shell scripts that are capable of running against a ksh or bash shell, and they make use of arrays. I created a function named "setArray" that interrogates the running shell and determines what builtin to use to create the array - for ksh, set -A, for bash, typeset -a. However, I'm having some issues with the bash portion.

The function takes two arguments, the name of the array and the value to add. This then becomes ${ARRAY_NAME} and ${VARIABLE_VALUE}. Doing the following:

set -A $(eval echo \${ARRAY_NAME}) $(eval echo \${${ARRAY_NAME}[*]}) "${VARIABLE_VALUE}"

works perfectly in ksh. However,

typeset -a $(eval echo \${ARRAY_NAME})=( $(eval echo \${${ARRAY_NAME}[*]}) "${VARIABLE_VALUE}" )

does not. This provides

bash: syntax error near unexpected token '('

I know I can just make it a list of strings (e.g. MYARRAY="one two three") and just loop through it using the IFS, but I don't want to lose the ability to use an array either.

Any thoughts ?

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    typeset makes a variable local to the scope when you use it. That variable will not exist outside that function. Also why eval? And using [*] instead of quoted [@] means your array values can't include spaces (and that shell glob characters will get expanded). Commented Mar 10, 2015 at 15:53
  • Looking at linux.die.net/man/1/bash to find the syntax of the typeset -a I'm not seeing the parens. On the other hand, looking in the Arrays section of that same page it appears that simply var=(val1 val2 val3) does work. Haven't used arrays recently in bash so I'm just quoting the manual, but that would be where i would start. Commented Mar 10, 2015 at 15:59
  • I've tried it without the eval as well and it doesn't work - for example: typeset -a ${ARRAY_NAME} Commented Mar 10, 2015 at 15:59
  • Do you need this function at all? Does ksh not support array+=("newvalue")? Commented Mar 10, 2015 at 15:59
  • newer versions of ksh might but I'm hindered by ksh88 on old AIX boxes Commented Mar 10, 2015 at 16:01

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Given the assertion that the ksh portion of this function is working only the bash portion needs to be created. For which the following should work and, I believe, be safe and robust (though evidence to the contrary is welcome).

eval $ARRAY_NAME+=\(\"\$VARIABLE_VALUE\"\)

First expansion only expands $ARRAY_NAME to get

eval array+=("$VARIABLE_VALUE")

which eval then causes to be evaluated again normally.

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