colons.sh

Object oriented programming in bash. You heard it right; OOP for Bash!

Usage

# @file my-app.sh

source /path/to/colons.sh

# Since we sourced colons.sh we can now use the new OOP keywords "new" and "as" as follows:
new Student as student

$student.on_board

$student.send_email "Welcome abroad!"

echo Boarding for $($student.get_name) is complete.

#!/usr/bin/env bash

# @file Student.class.sh

class Student extends User && {

  function on_board {
    read -p "What is your name? " input
    $this.__set name $input

    read -p "What is your email? " input
    $this.__set email $input
  }

  # Here we override User::send_email
  function send_email {
    local subject=$1
    EXTERNAL_IP=1 mail -s $subject $($this.__get email)
  }
}

#!/usr/bin/env bash

# @file User.class.sh

class User && {

  declare -i uid=0

  function __construct {
    $this.__set uid $((uid+=1))
  }

  function send_email {
    local subject=$1
    mail -s $subject $($this.__get email)
  }

  function get_name {
    printf '%s <%s>' $($this.__get name) $($this.__get email)
  }
}

This is how you can code in bash now!

Example

Check out ./example for a working example:

$ cd ./example
$ ./app.sh

Objects

Instantiation

#!/usr/bin/env bash

new Book as notebook
# Creats object $notebook an instance of Book class.

Method invokation

#!/usr/bin/env bash

$notebook.annotate $notes
# Invokes method 'annotate' on $notebook with sending $notes as the first parameter

Setting and Getting properties

#!/usr/bin/env bash

$notebook.__set title 'Scraps'
# Sets 'Scraps' as the value for the property 'title' for the object $notebook

echo $($notebook.__get title)
# Prints the value of the 'title' property on the object $notebook

Classes

Class definition

Every class needs to be defined in a file called [CLASS].class.sh

#!/usr/bin/env bash

# @file GeneralClass.class.sh

class GeneralClass && {
  ...
}

Inheritance

#!/usr/bin/env bash

# @file MyClass.class.sh

class MyClass extends GeneralClass && {

  function process() {
    local name=$1
    # ...
  }
}