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Hierarchy Markup Language, or less verbose xml.

hml

Hierarchy Markup Language, or less verbose xml.

Quickstart

node(property="value", other="another value"): this is the content
  child: content of the child
  child2
  	child21(prop="v1")
  child3(prop="v3"): another content

var node = HmlParser.Default.Parse(hmlContent).Root;
var other = node["other"]; //another value
var child = node.First(); 
var text = child.Text; //content of the child

Usage

Writing a document

An hml document should be structured following those rules :

• A unique root node
• One node per line
• A node must have a name
• A node can have properties
• A node property must have a key and a string value.
• A node can have text content
• The parent of a node is the first node in the tree that has an indentation level lower than the current node (except for the first one in the document which the root node)

Parser

The parser will load an hml content as an HmlDocument, which is a tree of HmlNode.

Loading a document from a string

var hml = "node(property=\"value\"): sample\n child: test";
var document = HmlParser.Default.Parse(hml);

Accessing nodes

HmlNode node = document.Root;
HmlNode child = node[0];

Accessing properties

string value = node["property"];

Accessing text

string text = node.Text;

Lexer

The lexer splits a document into tokens. You shouldn't use the lexer until you want to analyze the document structure more precisely (for example for pretty printing an hml document).

Loading tokens

var hml = "node(property=\"value\")";
HmlToken[] tokens = HmlLexer.Default.Tokenize(hmlContent);

Accessing tokens

var nodeName = tokens[0];
var startProperties = tokens[1];
var propertyName = tokens[2];
var equals = tokens[3];
var propertyValue = tokens[4];
var endProperties = tokens[5];

Accessing token data

var type = nodeName.Type; // HmlTokenType.Identifier
var content = nodeName.Content; // "node"
var line = nodeName.Position.Line; // 0
var column = nodeName.Position.Column; // 0

Parsing exceptions

In case of a parsing error an HmlParsingException that will contains token information (position in content, expected token, ...).

Specification

A .hml describe a tree where each node has a name, set of properties (with a name and a string value), a value (string), a list of descendants.

• Node : <Indent>``<Name>``<Properties>? (: <Text>)?
• Indent : ( )*
• Whitespaces : ( )*
• Name : <Letter>|_``<Letter>|<digit>|.|_|-*
• Properties : (``<Property>(,``<Property>)*)
• Property : <Name>``=``"``<Value>``"
• Value : (^")*
• Text : (^\r|^\n|^\r\n)*

About

You might guess why I felt the need for a new data description model while there is already JSON, XML, YAML and so on. Because I like XML for the way its describing a tree of elements, but I find it may be too verbose. For example, I liked the simplicity of template engines like pug.

Contributions

Contributions are welcome! If you find a bug please report it and if you want a feature please report it.

If you want to contribute code please file an issue and create a branch off of the current dev branch and file a pull request.

License

MIT © Aloïs Deniel