This one line command: paste <(printf "%s\n" "${!foo[@]}") <(printf "%s\n" "${foo[@]}") Will render: 12 bar 35 baz 42 foo bar baz Explained You can think of an array is a variable that can store multiple variables within it. To iterate over the key/value pairs you can do something like the following example # For every… If the index number is @ or *, all members of an array are referenced. Bash does not support multi-dimensional arrays, but there is a way to imitate this functionality, if you absolutely have to. bash documentation: Accessing Array Elements. Any solution that tries to handle the output of declare -p (typeset -p) has to deal with a) the possibility of the variables themselves containing parenthesis or brackets, b) the quoting that declare -p has to add to make it's output valid input for the shell.. For example, your expansion b="${a##*(}" eats some of the values, if any key/value contains an opening parenthesis. You can traverse through the array elements and print it, using looping statements in bash. Elements in arrays are frequently referred to by their index number, which is the position in which they reside in the array. array … In this article, we’ll cover the Bash arrays, and explain how to use them in your Bash scripts. Bash Arrays # Bash supports one-dimensional numerically indexed and associative arrays types. Hi Guys, I have an array which has numbers including blanks as follows: 1 26 66 4.77 -0.58 88 99 11 12 333 I want to print a group of three elements as a different column in a file as follows:(including blanks where there is missing elements) for.e.g. Using [@] each element of the array is expanded into a separate quoted argument, while [*] expands to a single quoted argument of all elements -- with each element separated by the first character of the IFS variable (i.e. I've added one value with spaces: foo=() foo[12]="bar" foo[42]="foo bar baz" foo[35]="baz" I, for quickly dump bash arrays or associative arrays I use. There are different ways to print the whole elements of the array. You can only use the declare built-in command with the uppercase “-A” option.The += operator allows you to append one or multiple key/value to an associative Bash array. Print the Whole Bash Array. You don't need this declare -p command in your real script. Arrays are one of the most used and fundamental data structures. echo is easy to use and mostly it fits our needs without any problem. In Bash, there are two types of arrays. These index numbers are always integer numbers which start at 0. There are the associative arrays and integer-indexed arrays. The values of an associative array are accessed using the following syntax ${ARRAY[@]}. When writing a bash scripts most of us by default use echo command as means to print to standard output stream. Bash arrays have numbered indexes only, but they are sparse, ie you don't have to define all the indexes. Bash Associative Array (dictionaries, hash table, or key/value pair) You cannot create an associative array on the fly in Bash. @nath declare -p is just a quick way to make bash print the real array (index and contents). This is also the case with echo command. However, with simplicity very often comes limitation. Simple one line trick for dumping array. 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