What specifically is your concern about the script being "easily modified" here? Associative arrays (sometimes known as a "hash" or "dict") use arbitrary nonempty strings as keys. Bash associative array in function. Copying associative arrays is not directly possible in bash. My problem is when ${USER_PARAMETERS_KEYS[j]} becomes equal to dstIPField since it has an empty string value in the associative array, so the if condition is not satisfied although the key is there. You could use the same technique for copying associative arrays: arrays bash associative-array I've declared match in my main function and I need to use this in another function which looks like this: In other words, associative arrays allow you to look up a value from a table based upon its corresponding string label. Name references are available in bash since release 4.3. In this article, we will explain how you can declare and initialize associative arrays in Linux bash. 1. Example: You can use the += operator to add (append) an element to the end of the array. The best solution probably is, as already been pointed out, to iterate through the array and copy it step by step. Associative arrays are always unordered, they merely associate key-value pairs. I'm trying to replicate this function I've written in Python that prints a message based on the player and opponents move and compares those moves with an associative array called match. Bash supports both regular arrays that use integers as the array index, and associative arrays, which use a string as the array index. If you agree with that, then you probably won't want to read about the "new" associative arrays that were added in version 4.0 of bash. 0,1 doesn't mean anything special in associative arrays, that's just the string 0,1. Bash Associative Arrays by Mitch Frazier. How can I pass a key array to a function in bash? It's not like bash internally creates a row for 0 with columns labelled 1 and 0. You just need to add two lines for each function addition, so I'd call that easily modified. Bash return an associative array from a function and then pass that associative array to other functionsHelpful? Data structures other than strings can't really be passed around between shell functions. The bash man page has long had the following bug listed: "It's too big and too slow" (at the very bottom of the man page). Bash, however, includes the ability to create associative arrays, and it treats these arrays the same as any other array. Associative arrays are an abstract data type similar to dictionaries or maps. There is another solution which I used to pass variables to functions. How to pass an associative array as argument to a function in Bash , I had exactly the same problem last week and thought about it for quite a while. Enter the weird, wondrous world of Bash arrays. We will further elaborate on the power of the associative arrays with the help of various examples. 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