dictionaries were added in bash version 4.0 and above. Method 1: In this method, traverse the entire associative array using foreach loop and display the key elements. An associative array lets you create lists of key and value pairs, instead of just numbered values. Using a C-style for loop, it loops through the associative array named ARRAY using the associative array's keys and outputs both the key and values for each item. There is no maximum limit on the size of an array, nor any requirement that members be indexed or assigned contiguously. Awk supports only associative array. Also, array indexes are typically integer, like array[1],array[2] etc., Awk Associative Array. THE_LIST=( "'item1' 'data1 data2'" "'item1' 'data2 data3'" "'item2' 'data4'" ) Based on the above, I want to create an associative array that would assign itemN as key and dataN as value.. My code iterates over the list, and assigns key => value like this (the additional function is shortened, as it performs some additional jobs on the list): Program: Program to loop through associative array and print keys. You can use any string or integer as a subscript to access array elements.The subscripts and values of associative arrays are called key value pairs. One of the advantages of zsh over bash 3 is the support of “associative arrays,” a data structure known as hash tables or dictionaries in other languages. Any variable may be used as an indexed array; the declare builtin will explicitly declare an array. It then uses this sorted array to loop through the associative array ARRAY. You can assign values to arbitrary keys: $ They work quite similar as in python (and other languages, of course with fewer features :)). The live ISO reports the exact same version of bash--4.2.46(2)-release (x86_64-redhat-linux-gnu)--but parses the keys correctly. Bash provides one-dimensional indexed and associative array variables. In some programming languages, arrays has to be declared, so that memory will be allocated for the arrays. Copying associative arrays is not directly possible in bash. For example, the associative array userinfo has multiple values, each identified with a key: Keys are unique and values can not be unique. A detailed explanation of bash’s associative array Bash supports associative arrays. There is another solution which I used to pass variables to functions. It sorts the associative array named ARRAY and stores the results in an indexed array named KEYS. I've got an array that contains duplicate items, e.g. Dictionary / associative arrays / hash map are very useful data structures and they can be created in bash. In associative array, the key-value pairs are associated with => symbol. The best solution probably is, as already been pointed out, to iterate through the array and copy it step by step. You could use the same technique for copying associative arrays: Steps To Reproduce Install the minimal install, log in, create an associative array with one of the special characters: They are one-to-one correspondence. Let's see an example: We will go over a few examples. This is not a complicated subject, but you have to be careful when writing your code because you will have extra brackets, braces, … Introduction to bash arrays and bash array operations. Deleting an element from the array To delete an element from the array we need to know it's index or its key in the case of an associative array, and use the unset command. To check the version of bash run following: Bash, however, includes the ability to create associative arrays, and it treats these arrays the same as any other array. In associative arrays, you can store a piece of data, or value with an identifying ‘key’. Today, I’m going to give you some examples on how to work with associative arrays in bash / ksh. 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