AAL as Intentional Programming System

How to use AAL as Intentional Programming System.

Content of this chapter:

   Topics
   Internal Architecture
   Builin Attributes
   User defined Attributes
   Type Library interface
   Extend Language
   Language switch
   Code Weafer
   Implementation Issues
     Multipass Parser
   Links

Topics

Multipass Parser.
Parser allows ambiguitys.
Parsing allows to modify the Parse Tree.
Nodes has Attributes to identify the level of Parse/Interpret/Compile pass.

Internal Architecture

Language definition levels:

Abstract Parse Syntax definition (ParseNode). -> generates an Abstract Code Tree (Code).
Code -> Semantic analysis. -> mapps semantic to Object Representation (ClazzInfo). -> generates SymbolTable . -> generates OpCodes.
OpCode. -> stack based operations. -> can be executed using ClazzInfo.

Builin Attributes

String s = new [StackAlloc] String("asdf");

User defined Attributes

void foo(int i)
{
}
[
compiler.findNode("FunctionDecl").getType().attatchAttribute("Key", "Value);
]

Type Library interface

[
compiler.loadTypeLib(new JavaLib("java/net"));
// all classes of java.net are available
]
java.net.SocketServer ss = new java.net.SocketServer();

[
  compiler.pushGrammar(); // make new scope block for the grammar
  compiler.registerRule("RegExpExpr", new RegExp("Expression [ '=~' REGEX_EXPRESSION ]" ));
  compiler.replaceRule("Expression", "RegExpExpr");
]  // now this new Grammar element is available
  ("asdf" + b) =~ /asdf/;
[
  // remove the Grammar defintion.
  compiler.popGrammar();
]

Language switch

[
compiler.registerToken("END_OF_LISP", "<<EndOfLisp");
compiler.replaceGrammarUntil(new LispInterpreter(), "END_OF_LISP");
]
(defun x (a b) (+ a b))
<<EndOfLisp

acdk.lang.System.println("now back in ACDK");
// using the method defined in lisp
acdk.lang.System.println(x(1, 2));

Code Weafer

[
  Code logAdder = new LogInOutAdder(orgRule: compiler.getRule("FunctionBody"), classname: "MyClass", funcname: "foo");
  compiler.replaceRule("FunctionBody", locAdder);
]

class MyClass
{
  public void bar() {}
  public int foo(int i)
  {
    // LogInOutAdder whould insert a statement to print out something like "MyClass.foo(42) entered"
    return i + 1;
  }
}

Implementation Issues

Multipass Parser

PassLevel:

Abstract Syntax Tree (AST): Context Free Tree with Rules and Token
Language Syntax Tree (LST): AST, but fixed ambiguities.
Semantik Resolution Tree (SRT): Based on the LST Check and fix semantic issues. For example the construct

Object o = "asdf";
o.length(); // this line will be explained

Will translated from Rule "Expression Operator('.') Function" to "Expression" DmiObjFuncCall Function in case the o is a Object available via DMI functionality. Inlining, static overloading, etc. may be resolved here.
Interpret Syntax Tree (IST): Does interpret the code.
CodeGen Syntax Tree (CST): Does generate byte code or asm.

class AClass
{
  void foo();
} // commit point to generate LST here fore the class Rule.

[ // AClass as LST definition is alrady available
  compiler.dosomething();
  // has to be interpreted.
]

Maybe the transforming from Source to AST to LST to IST and CST may be restarted by one Rule, because it modified the ST.