bash not in array

Elements in arrays are frequently referred to by their index number, which is the position in which they reside in the array. There is no maximum limit on the size of an array, nor any requirement that members be indexed or assigned contiguously. No, you need not count them all. These index numbers are always integer numbers which start at 0. Unlike in many other programming languages, in bash, an array is not a collection of similar elements. Print all elements, each quoted separately. In BASH script it is possible to create type types of array, an indexed array or associative array. An array is a variable that can hold multiple values, where each value has a reference index known as a key. Example: echo "${array[@]}" Print all elements as a single quoted string Bash Array – An array is a collection of elements. Arrays are indexed using integers and are zero-based. We can combine read with IFS (Internal Field Separator) to define a delimiter. As a quick example, here’s a data table representing a two-dimensional array. We can display the length of the whole array or any array element by using a special operator '#'. bash documentation: Accessing Array Elements. In Bash, there are two types of arrays. By asking for indexes not in the array you either create an array with indexes missing, ie 0,1,3,6,7,9 This would then mean you have "holes" at positions - 2,4,5,8 and nothing in any index after 9 However, you create your array using the following: Arrays in Bash. Instead, bash provides a special operator who does all the work for us. This is a pretty common problem in bash, to reference array within arrays for which you need to create name-references with declare -n.The name following the -n will act as a nameref to the value assigned (after =).Now we treat this variable with nameref attribute to expand as if it were an array and do a full proper quoted array expansion as before. Since bash 4.3 it is not that easy anymore. There are the associative arrays and integer-indexed arrays. Now the myarray contains 3 elements so bash split string into array was successful # /tmp/split-string.sh My array: string1 string2 string3 Number of elements in the array: 3 . Bash does not support multi-dimensional arrays, but there is a way to imitate this functionality, if you absolutely have to. When using arrays, one must know how many elements are present in the array. As if this was not complicated enough, with "declare -p", you do not get the type or the original variable. Any variable may be used as an array; the declare builtin will explicitly declare an array. Bash arrays have numbered indexes only, but they are sparse, ie you don't have to define all the indexes. Since bash does not discriminate string from a number, an array can contain a mix of strings and numbers. The Bash provides one-dimensional array variables. 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