Delete-Key-**Friendly**. Instead of introducing packages, includes, compilers, etc., we propose using [`main.sh`](http://bash3boilerplate.sh/main.sh) as a base and removing the parts you don't need.
- Simple command-line argument parsing that requires no external dependencies. Definitions are parsed from help info, ensuring there will be no duplication
- Logging that supports colors and is compatible with [Syslog Severity levels](http://en.wikipedia.org/wiki/Syslog#Severity_levels), as well as the [twelve-factor](http://12factor.net/) guidelines
Even though this option introduces a Node.js dependency, it does allow for easy version pinning and distribution in environments that already have this prerequisite. This is, however, entirely optional and nothing prevents you from ignoring this possibility.
As of `v1.0.3`, b3bp offers some nice re-usable libraries in `./src`. In order to make the snippets in `./src` more useful, we recommend the following guidelines.
It is nice to have a Bash package that can not only be used in the terminal, but also invoked as a command line function. In order to achieve this, the exporting of your functionality *should* follow this pattern:
1. In functions, use `local` before every variable declaration.
1. Use `UPPERCASE_VARS` to indicate environment variables that can be controlled outside your script.
1. Use `__double_underscore_prefixed_vars` to indicate global variables that are solely controlled inside your script, with the exception of arguments that are already prefixed with `arg_`, as well as functions, over which b3bp poses no restrictions.
1. Use long options (`logger --priority` vs `logger -p`). If you are on the CLI, abbreviations make sense for efficiency. Nevertheless, when you are writing reusable scripts, a few extra keystrokes will pay off in readability and avoid ventures into man pages in the future, either by you or your collaborators. Similarly, we prefer `set -o nounset` over `set -u`.
1. Use `{}` to enclose your variables. Otherwise, Bash will try to access the `$ENVIRONMENT_app` variable in `/srv/$ENVIRONMENT_app`, whereas you probably intended `/srv/${ENVIRONMENT}_app`. Since it is easy to miss cases like this, we recommend that you make enclosing a habit.
1. Use `set`, rather than relying on a shebang like `#!/usr/bin/env bash -e`, since that is neutralized when someone runs your script as `bash yourscript.sh`.
1. Use `#!/usr/bin/env bash`, as it is more portable than `#!/bin/bash`.
1. Use `${BASH_SOURCE[0]}` if you refer to current file, even if it is sourced by a parent script. In other cases, use `${0}`.
1. Use `:-` if you want to test variables that could be undeclared. For instance, with `if [[ "${NAME:-}" = "Kevin" ]]`, `$NAME` will evaluate to `Kevin` if the variable is empty. The variable itself will remain unchanged. The syntax to assign a default value is `${NAME:=Kevin}`.
We are looking for endorsements! Are you also using b3bp? [Let us know](https://github.com/kvz/bash3boilerplate/issues/new?title=I%20use%20b3bp) and get listed.
