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SDLang

Simple Declarative Language

SDLang is a simple and concise way to textually represent data. It has an XML-like structure – tags, values and attributes – which makes it a versatile choice for data serialization, configuration files, or declarative languages. Its syntax was inspired by the C family of languages (C/C++, C#, D, Java, …).

// This is a node with a single string value
title "Hello, World"
// Multiple values are supported, too
bookmarks 12 15 188 1234
// Nodes can have attributes
author "Peter Parker" email="peter@example.org" active=true
// Nodes can be arbitrarily nested
contents {
	section "First section" {
		paragraph "This is the first paragraph"
		paragraph "This is the second paragraph"
	}
}
// Anonymous nodes are supported
"This text is the value of an anonymous node!"
// This makes things like matrix definitions very convenient
matrix {
	1 0 0
	0 1 0
	0 0 1
}

Implementations

• 
  SDLangNET

  An updated .NET fork of the original SDL.NET library

  SDL.NET

  The original .NET implementation of SDLang
• 
  SingingBush/SDL

  An up-to-date Java fork of the original SDL library

  ikayzo/SDL

  The original Java implementation of SDLang
• 
  libsdlang

  C implementation of an SDLang parser using a Ragel based state machine
• 
  SDLite

  A fast and lightweight parser/generator implementation

  SDLang-D

  The first parser/generator implementation for D
• 
  php-sdl

  PHP implementation of a parser/generator
• 
  SDL.rb

  Ruby version of the original SDLang implementation
• 
  SDL-dart

  An SDLang parser written in Dart (also usable in JavaScript with dart2js)
• 
  HDJ

  A parser implementation for Haskell

Data types

// Strings
"String \"with escape support\""
`String "without escape support"`
// Numbers
10    // 32-bit integer
10L   // 64-bit integer
10.5  // 64-bit float (double)
10.5d // 64-bit float
10.5f // 32-bit float
10.123BD  // 128-bit decimal
// Boolean and null values
true  // boolean true
false // boolean false
on    // boolean true
off   // boolean false
null  // a null value
// Date/time formats
2015/12/06 12:00:00.000-UTC // Date/time value (UTC timezone)
2015/12/06 12:00:00.000     // Date/time value (local time)
2015/12/06                  // Date value
12:14:34     // Duration: 12 hours, 14 minutes, 34 seconds
12:14:34.123 // 12 h, 14 min, 34 s, 123 ms
2d:12:14:34  // 2 days, 12 h, 14 min, 34 s
// Binary data (Base64 encoded)
[sdf789GSfsb2+3324sf2]

Comment styles

// C++ style
/*
C style multiline
*/
tag /*foo=true*/ bar=false
# Shell style
-- Lua style

Syntax details

// Trailing semicolons are optional
title "Some title";
// They can be used to separate multiple nodes
title "Some title"; author "Peter Parker"
// Tags may contain certain non-alphanumeric characters
this-is.1_valid$Tag-Name
// Namespaces are supported
renderer:options "invisible"
physics:options "nocollide"
// Nodes can be separated into multiple lines
title \
	"Some title"
	
	

Tools

• SDLang HTML syntax highlighter
• Syntax highlighting plug-in for Sublime Text
• Syntax highlighting plug-in for Atom
• Major mode for Emacs
• Experimental VIM syntax file

Who uses SDLang? 1

• 
• 
• 
• 
• JTest

References

• Language Reference
• Website issue tracker/Contact
• Original homepage (mirror)
• Original Reference (mirror)