Python vs Bash

Thu, 02 Feb 2023 12:00:00 +0000

Recreated in October 2026 from the post; the original image was lost

Python and bash are both programming languages, but they have different purposes and use cases.

Bash: Named Reference

Wed, 02 Mar 2022 12:00:00 +0000

Bash is different world. Powerful, simple, elegant and complex all at the same time. Recently while trying to reduce the burden of repetitive code, I was trying to check what can be done to use references in Bash (something like pointers) and it was an interesting problem that I enjoyed solving.

Notes: For self

Wed, 23 Feb 2022 07:27:42 +0000

Bash is a string oriented language
We do not write step=$((step++)) this expression will return a numeric value which the shell will then take as the command to to be executed.
No spaces are allowed around the equal sign for variable assignment.
let "step++" is same as (( step++ ))
Use declare to set variable values and attributes

In bash = and == both mean the same thing

💬 What is the difference between [ and [[?

•
if cd $dir; then
In this case the command cd $dir will be executed and based on success or failure of the command executed the if or else part will be executed respectively.
if [$dir]; then
```
<span
 class="absolute top-0 w-6 transition-opacity opacity-0 -start-6 not-prose group-hover:opacity-100 select-none">
 <a class="text-primary-300 dark:text-neutral-700 !no-underline" href="#if-dir-then" aria-label="Anchor">#</a>
</span>
```
Single bracket is equivalent to test command evaluate conditional expression
1. •
  < & >
  - Within [ compare using simple ASCII ordering & within [[ comparison is lexicographic.
  - Within [ you have to escape \> to avoid redirection.

💬 BC is a language?

 <span></span>
</span>
<span class="accordion-chevron ms-auto flex h-5 w-5 items-center justify-center print:hidden">
 <span class="relative block icon"><svg

xmlns=“http://www.w3.org/2000/svg" viewBox=“0 0 20 20” fill=“currentColor” aria-hidden=“true”

💬 Supports arbitrary precision numbers with interactive execution of statements. (Command line)

awk provides filtering capabilities

> printf 'gate\napple\nwhat\nkite\n' | awk '/at/'

gate
what

printf 'gate\napple\nwhat\nkite\n' | awk '!/e/'

what

awk is primarily used for field based processing

One liner structure awk 'cond1{action1} cond2{action2} … condN{actionN}'

Bash on Samarthya

Python vs Bash

Bash: Named Reference

Notes: For self

if cd $dir; then

`if [$dir]; then`

`<span class="absolute top-0 w-6 transition-opacity opacity-0 -start-6 not-prose group-hover:opacity-100 select-none"> <a class="text-primary-300 dark:text-neutral-700 !no-underline" href="#if-dir-then" aria-label="Anchor">#</a> </span>`

< & >

Bash on Samarthya

Python vs Bash

Bash: Named Reference

Notes: For self

if cd $dir; then

if [$dir]; then <span class="absolute top-0 w-6 transition-opacity opacity-0 -start-6 not-prose group-hover:opacity-100 select-none"> <a class="text-primary-300 dark:text-neutral-700 !no-underline" href="#if-dir-then" aria-label="Anchor">#</a> </span>

< & >

`if [$dir]; then`

`<span class="absolute top-0 w-6 transition-opacity opacity-0 -start-6 not-prose group-hover:opacity-100 select-none"> <a class="text-primary-300 dark:text-neutral-700 !no-underline" href="#if-dir-then" aria-label="Anchor">#</a> </span>`