Array iteration for loops

We can iterate over arrays conveniently in bash using for loops with a specific syntax. We can use the special variables in BASH i.e @ to access all the elements in the array. Let’s look at the code:

#!/bin/bash

s=("football" "cricket" "hockey") 
for n in ${s[@]}; 
do
    echo $n
done

We can iterate over the array elements using the @ operator that gets all the elements in the array. Thus using the for loop we iterate over them one by one. We use the variable ${variable_name[@]} in which, the curly braces here expand the value of the variable “s” here which is an array of strings. Using the [@] operator we access all the elements and thus iterate over them in the for a loop. Here, the “n” is the iterator hence, we can print the value or do the required processing on it. 

Since BASH is a command-line language, we get some pretty feature-rich experience to leverage the programming skills to perform tasks in the terminal. We can use loops and conditional statements in BASH scripts to perform some repetitive and tricky problems in a simple programmatic way. In this article, we are going to focus on the for loop in BASH scripts.

Depending on the use case and the problem it is trying to automate, there are a couple of ways to use loops.

• Simple For loop
• Range-based for loop
• Array iteration for loops
• C-Styled for loops
• Infinite for loop