Indexed Arrays

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Indexed Arrays

Indexed Arrays

An indexed array uses numeric indices starting at 0, and indices don't have to be contiguous — you can assign arr[5]=value without ever setting indices 0–4. ${arr[@]} expands to all elements, and ${!arr[@]} expands to all the indices currently in use. This flexibility is unique to Bash's indexed arrays compared to fixed-size arrays in other languages.

Note: ${!arr[@]} lists the indices actually in use, which matters when an array has gaps.

Example: Indexed Arrays

bash

#!/bin/bash
colors=("red" "green" "blue")
colors[5]="purple"

for i in "${!colors[@]}"; do
    echo "Index $i: ${colors[$i]}"
done

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Array Basics
Indexed Arrays in Depth
Indexed Arrays
Associative Arrays
Array Slicing
Array Length
Iterating Arrays
Looping Arrays
Array Length and Removing Elements
Reading Command Output Into an Array

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Indexed Arrays

Indexed Arrays

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