Set Env Vars with Shell Scripts

Sometimes I have limited screen real estate in my terminal, and my normal prompt of current/working/directory (git_branch) % takes up too much space. I wanted a bash script that could change my prompt to something short like & in one quick command. So I wrote a shell script:

#!/bin/bash

PS1="\[\e[32m\]& \[\e[m\]"

Nice and simple, right?

~/src/dotfiles (main) % ./shorter.sh
~/src/dotfiles (main) % 

Except, it doesn't change anything 😱. That's because changing PS1 isn't executing a command, it's setting an environment variable. So, just executing this shell script isn't enough, we need to source it to source the new PS1 in this terminal.*

~/src/dotfiles (main) % . ./shorter.sh
& 

* This is also why changing the prompt like this only affects the current terminal, and not any others that you may have open at the same time.

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