Getting started with Bashgenn

Installation

First of all, we want to install RBGN, the interpreter of Bashgenn. To install RBGN, install Rust and then run this command (works cross-platform):

cargo install rbgn

Hello, World!

Create a file named hello_world.bgn and open it in your favorite editor. We do it in Nano:

nano hello_world.bgn

Put this contents into the file:

- Lines starting with a hyphen (-) are comments in Bashgenn.
- Please note that you can't place a comment after a command.
- You need to add comments to separate lines

- This sets the `hello` variable to `Hello, World`.
STATIC_STR_VAR hello Hello, World!

- This writes the contents of the `hello` variable to the standard output.
ECHO hello

Save the file. In Nano, you can save and close the file by pressing Ctrl+X, Y and then Enter. Then, run the script using this command:

rbgn -i hello_world.bgn

It will print Hello, World! to the output.

Practice 1 - Hello, Bashgenn!

Now, create a program that prints Hello, Bashgenn! to the output.

STATIC_STR_VAR hello_bg Hello, Bashgenn!
ECHO hello_bg

Reading input

We can also read input and write it to the output:

- READ reads one line of input into a variable
READ my_variable
ECHO my_variable

We can also read two lines of input and write them:

READ my_variable
ECHO my_variable
READ your_variable
ECHO your_variable

Practice 2 - Reversing lines

Now, create a program that reads two lines of input and writes them in reversed order.

READ my_variable
READ your_variable
ECHO your_variable
ECHO my_variable

Moving characters

To write the last character from a variable, use the LAST command (this also removes the character from the variable):

STATIC_STR_VAR hello Hello, World!

- This prints `!`
LAST hello

Loops

We can also do something forever:

STATIC_STR_VAR hello Hello, Bashgenn!

FOREVER
  ECHO hello
DONE

Practice 3 - Repeating input

Now, create a program that reads one line of output and writes it forever.

READ my_variable

FOREVER
  ECHO my_variable
DONE

Please note that you can't have nested loops because of the bug in RBGN.