Cirru.org

IPA: /ˈsɪɹə/

Writing code in syntax tree

Home page: http://cirru.org

Twitter: https://twitter.com/cirrulang

Why Cirru?

In programming languages, symbols(like brackets) make lexing and paring simpler, indentations make code readable. And this may lead to really tricky syntaxes.

I want people just write code by editing the syntax tree. So there should be a small language showing us how does it work.

What is Cirru?

The name "Cirru" came from cirrus cloud. I read it like cirrus(but without s).

The core of Cirru is the indetation-based syntax:

• use prefix syntax, see Lisp
• () to create expressions inside each line, see Lisp
• indetation with 2 spaces
• represent token with optional "" and \, see Bash
• $ as a function to fold code, see Haskell
• , as a function to unfold code

Cirru prefers Lisp's notions to make itself minimalistic:

• Code is data
• Syntax represents AST

Examples

These examples below are identical:

set a (add (number 1) (numer 2))

set a $ add (number 1) $ number 2

set a $ add
  number 1
  number 2

set a
  add
    number 1
    number 2

Find more examples at cirru-parser.

Usage

While that is simple, there are many subprojects around Cirru, such as:

• CirruScript: compiled-to-js language
• interpreter: a demo of scripting language in Go
• Cirru Editor: graphical syntax tree editor