Pure Javascript YAML library that supports both dump and load? [duplicate]

Question

This question already has an answer here:

• JavaScript YAML Parser 4 answers

Does such a thing exist for YAML (aka YAML)?

If this existed at one time, it must have been obliterated because the latest search turned up nada. It looks like there are plenty of implementations that dump from Javascript to YAML output only, but having trouble finding an implementation that supports both dump and load.

Is anyone working on such a thing ... or is the demand simply far too low for this.

Answer 1

Possibly newer version of js-yaml here:

http://github.com/visionmedia/js-yaml

Answer 2

Was just looking for the same, here's a basic Javascript-based YAML parser written by Tj Holowaychuk over at refactormycode.com. I'm duplicating it here to ensure it isn't lost, appears the JsYaml link on yaml.org has been broken a while. Haven't tested it yet.

;(function(){
  YAML = {
    valueOf: function(token) {
      return eval('(' + token + ')')
    },

    tokenize: function(str) {
      return str.match(/(---|true|false|null|#(.*)|\[(.*?)\]|\{(.*?)\}|[\w\-]+:|-(.+)|\d+\.\d+|\d+|\n+)/g)
    },

    strip: function(str) {
      return str.replace(/^\s*|\s*$/, '')
    },

    parse: function(tokens) {
      var token, list = /^-(.*)/, key = /^([\w\-]+):/, stack = {}
      while (token = tokens.shift())
        if (token[0] == '#' || token == '---' || token == "\n") 
          continue
        else if (key.exec(token) && tokens[0] == "\n")
          stack[RegExp.$1] = this.parse(tokens)
        else if (key.exec(token))
          stack[RegExp.$1] = this.valueOf(tokens.shift())
        else if (list.exec(token))
          (stack.constructor == Array ?
            stack : (stack = [])).push(this.strip(RegExp.$1))
      return stack
    },

    eval: function(str) {
      return this.parse(this.tokenize(str))
    }
  }
})()

print(YAML.eval(readFile('config.yml')).toSource())




// config.yml

---
  # just a comment
  list: ['foo', 'bar']
  hash: { foo: "bar", n: 1 }
  lib:
    - lib/cart.js
    - lib/cart.foo.js
  specs:
    - spec/cart.spec.js
    - spec/cart.foo.spec.js
    # - Commented out
  environments:
    all:
      options:
        failuresOnly: true
        verbose: false

Answer 3

I update this question to give another solution that myself worked on: https://github.com/jeremyfa/yaml.js

It is a pure javascript port of Symfony YAML Component (YAML 1.2) and supports both loading and dumping. Hope this helps.

Answer 4

I'm not sure where the "plenty of implementations" that support dump but not load are to be found - to the extent that JSON is a proper subset of YAML 1.2, I guess there might be plenty of those, but that subset makes for YAML that is not particular human friendly, especially for complex data structures. Most of the links I have found are to github forks of JS-YAML that depend on node.js and/or only provide parsers.

Jeremy Faivre's yaml.js on bitbucket implements both dump and load of YAML in standalone javascript (I found it from an answer to a related stackoverflow question). It is not actively maintained, but seems to work fine for moderately complex YAML and/or javascript objects.

Answer 5

yaml-javascript pretends to be both dumper and parser. Never tried.

Answer 6

There's also this javascript-yaml-parser/

See this question: JavaScript YAML Parser, Diogo Costa says:
None of the javascript YAML parsers available satisfied my needs so I developed my own: It is available here: http://code.google.com/p/javascript-yaml-parser/