cirru-parser

Cirru Parser

Cirru is an indentation-based grammar. You may use it to create your own DSLs or scripting languages.

Find more at http://cirru.org/

Usage

npm install --save cirru-parser

{parse, pare} = require 'cirru-parser'

syntaxTree = parse code, filename
simplifiedTree = pare code, filename

info = caution char

• parse(code, filename):

Parse code in Cirru grammar, filename is optional:

A token in syntaxTree is like:

token =
  text: 'get'
  x: 0
  y: 0
  ex: 1
  ey: 1
  path: 'a.cirru'

And expressions here are just tokens in arrays, like:

expression = [
  token
,
  [
    token
  ,
    [
      token
    ]
  ]
]

• pare(code, filename):

pare is short for parse, filename is optional.

simplifiedTree does not contain informations of files, like line numbers, file content, which are needed in caution.

A token from pare is a string, i.e. the text field of parsing results.

Live demo

Demo: http://repo.cirru.org/parser/ . By typing on the left you should see the pare results on the right.

Grammar

Detailed examples can be found in cirru/ and ast/ directories.

For short, there are then rules of Cirru:

• It indents with 2 spaces
• Parentheses are closed in the same line it opened
• Strings are quoted with double quotes: "string"
• $ folds followed tokens in an expression
• , unfolds followed tokens in an expression

Parsing

Here's a Gist showing how it's parsed(not including the steps solving $ and ,):

https://gist.github.com/jiyinyiyong/bdda3f616ff0f1bea917

This method was developed in [the Go version][go], you may check it out here.

Development

Run tests:

gulp test

Also you may debug index.html in a browser after compiling the code:

npm i
gulp start
# view generated index.html in a web server

Changelog

0.10.1

• switch to ex, ey from $x, $y

0.10.0

• Rewritten with new solution from Go
• drop caution

License

MIT