wildlyinaccurate / hello-world

Hello, World! Is a programming language for writing hello world applications. And nothing else.

Hello, World!

Hello, World! Is a programming language for writing hello world applications. And nothing else.

Syntax

Hello, World!

The   Hello, World! token (two spaces, followed by the string "Hello, World!") will evaluate to the string "Hello, World!". This token is represented internally as a HelloVal. Once the interpreter parses a HelloVal, it will not parse anything else.

Comments

Since everything after a HelloVal is ignored, it is possible to document your programs with comments like so:

  Hello, World! This is a comment
  Hello, World! This is another, slightly more interesting comment
  Hello, World!

The program above will output the following:

Hello, World!
Hello, World!
Hello, World!

Boolean Logic

You can implement simple boolean logic by utilising the fact that anything other than a HelloVal is an error.

  Hello, World!
False
  Hello, World! This will never be evaluated

The above program will conveniently explode on the False statement, and output the following:

Hello, World!
Parse error at "your face" (line 1, column 1):
unexpected "F"

Installation

git clone https://github.com/wildlyinaccurate/hello-world.git
cd hello-world
caban sandbox init
cabal install
make

Usage

Hello, World! can be run as a REPL

$ ./bin/hello-world
hello=>   Hello, World!
Hello, World!
hello=> Hello, World!
Parse error at "lisp" (line 1, column 1):
unexpected "H"
expecting "  Hello, World!"
hello=> what even is this
Parse error at "lisp" (line 1, column 1):
unexpected "w"
expecting "  Hello, World!"

Or it can take programs directly

$ ./bin/hello-world '  Hello, World!'
Hello, World!

Why?

Shut your face.