Naturel v1.0.0 Nov 14 2008
Naturel (not to confuse with NATURAL) is a programming language that was developed by Ralph Erdt and Andreas Textor for the Compiler Construction class at the University of Applied Sciences Wiesbaden in winter semester 07/08. Naturel stands for "Naturel is the Andreas Textor Und Ralph Erdt Language" ("und" is the german word for "and").
We wrote a minimal standard library for Naturel and a compiler in Java that produces C code. The language is object-oriented and its syntax is inspired by C, Java, Pascal and UML. Many keywords that are not necessary for the semantics like class were left out and other keywords were replaced by symbols, like + instead of public. Comments are written like in Java and C++ using // and /* ... */. Methods and attributes can have the visibilities public, private and protected that are expressed using the UML-Modifiers +, - and #. A class variable uses a double modifier character instead of the keyword static. Overwriting of methods is allowed in Naturel, overloading is not allowed.
+a:num;	// public
-b:num;	// private
#c:num;	// protected
++d:num; // public static
--e:num; // private static
##f:num; // protected static
Naturel's grammar was transformed into a parser using the parser generator SableCC. The complete documentation, sample programs and source code of the compiler are contained in the downloadable package. The following block shows a short sample program that can be compiled using the compiler. num and str are the built-in data types for integers and strings, the static new method is the constructor of the class.
+Point {

	+getX():num { return(x); }
	+getY():num { return(y); }
	++new(px:num, py:num) { x := px; y := py; }

	+addPoint(p:Point) {
		x := x + p.getX();
		y := y + p.getY();

	+tostr():str {
		return("[" + x.tostr() + "," + y.tostr() + "]");

	++main(args:str[]):num {
		p1:Point :=, 2);
		p2:Point :=, 4);
		out("Point 1: " + p1.tostr() + "\n");
		out("Point 2: " + p2.tostr() + "\n");
		out("Point 1: " + p1.tostr() + "\n");
Note: Since the whole language including idea, grammar and compiler were created during a single semester, not all features are implemented in the compiler, especially a Garbage Collector is missing. Thus, Naturel should not be used in productive environments.