5 Bash Coding Techniques That Every Programmer Should Know

Use these coding techniques to write fast and readable shell scripts

Photo by Emile Perron on Unsplash, edited with Canva

Bash undoubtedly became every modern Unix-like or Unix-based operating system’s native, inbuilt automation solution. Programmers use Bash to automate their repetitive command-line tasks by creating shell scripts. The primary goal of Bash is to offer a minimal syntax to execute other programs and work with their exit codes and output. But, modern Bash interpreters come with a fully-featured command language that offers most general-purpose programming language features. So, we can write highly-readable shell scripts by including traditional command-line invocations and algorithmic code. Modern Bash versions introduced associative arrays and performance-related features like pass-by-reference support to make Bash competitive with other shell-scripting-ready languages.

In this story, I will explain some Bash coding techniques you can include in your shell scripts to make them modern, fast, and readable. With these techniques, you can use Bash to write general-purpose programming or algorithm implementations, such as algorithm prototyping, implementing utility programs, or even competitive programming!

Using arrays in shell scripts

A traditional Bash variable typically has no type, but you can process it as an integer, decimal, or string according to a particular processing context. We usually use Bash variables to store command outputs, algorithm parameters, and other temporary values. Bash also supports two array types: one-dimensional (numerically indexed) and associative (key-value structure). Working with Bash arrays is easy as with other popular dynamically-typed general-purpose languages, such as Python, PHP, or JavaScript. See how to create arrays in Bash:

#!/bin/bash

numbers=(2 4 5 2)

declare -a words
words[0]='Orange'
words[1]='Pineapple'

echo ${numbers[@]} ${words[@]}

The above code outputs array contents as follows:

You can check the declaration of each array reference with the declare built-in as follows: