hcl/lang.txt

## dictionary list (DIC)
	{ 1 2 3 4 }
	{ 1: 2, 3: 4}
	{} -> empty dictionary
	{ 1 } -> error, no value.  dictionary requires even number of items.

## array list
	[ 1 2 3 4]
	[ 1, 2, 3, 4 ]
	[] -> empty array

## byte array list
	#[ 1 2 3 4 ]
	#[  1, 2, 3, 4 ]
	each item must be in the byte range.
	if a given value is not a number in the allowed range, an exception error is raised.
	(try
		(set a 20)
		#[ 1 2 3 (+ a 300)]  ; this throws an catchable exception.
	catch(e)
		(printf "EXCEPTION - %O\n" e)
	)

## non-executable list (QLIST)
	#(1 2 3 4)
	#(1 2 3 4 . 5)
	#() -> same as null
	comma not allowed to seperate items.

## varaible declaration list (VLIST)
	| a b c |


## class declaration with methods.

	(defclass X 

		| x y |                 ; instance variables 
		::: | bob jim |             ; class variables

		; instance variables and class variables must not collide with those of parent classes.
		; they must not collide with method names of parent classes
	
		(set bob "Bob")         ; can access class variables. disallowed to access instance variables

		(defun setX (a)
			(set x a)
		)

		; instance method. a method name must not collide with instance variable names and class variable names.
		; the name can be the same as method names of parent classes.
		(defun K (a b)
			(:self Y a)
			(return (+ a b x y))
		)
	
		(defun Y (a)
			(printf "Y=>%d [%s]\n" a bob) 
		)

		(defun ::: KK (a b)
			(printf "K=>%s\n" bob) ; a class method can access class variables but not instance variables
			(return (+ a b))
		)

		(set jim (lambda (a b) (+ a b))) ; an anonymous function created 
	)

	(set r (object-new X))
	(:r Y 10)
	(printf ">>%d\n" (:X KK 77 99))


## method invocation

send the message aaa to the receiver
	(:self aaa)

send the message aaa to the receiver but let it resolve the method in the superclass side.
	(:super aaa)

send the message dump to the object pointed to by x with arguments 1, 2, 3.
	(:x dump 1 2 3)

## method types

- class method


- class instantiation method

	(defclass P
		| x y |
		(defun ::* new ()
			(set x 1)	
			(set y 1)	
			(return self)
		)
		(defun get-x() x)
		(defun get-y() y)
	)
	(defclass X ::: P
		| x y |
		(defun ::* new (a b)
			(:super new)
			x = a
			y = b
			(return self)
		)
		(defun get-xx() x)
		(defun get-yy() y)
	)

	(set t (:X new 10 20)) ;t is an instance of X
	(printf "%d %d %d %d\n" (:t get-x) (:t get-y) (:t get-xx) (:t get-yy)) ; must print 1 1 10 20
	(:t new 100 300)  ;the x, y in the X part get reset to 100 and 300. doesn't create a new instance
	(printf "%d %d %d %d\n" (:t get-x) (:t get-y) (:t get-xx) (:t get-yy)) ; must print 1 1 100 300

- instance method



## dynamic dispatching by method name
	(defclass X
		(defun t1 (x) (printf "t1 = %d\n" (+ x x x)))
		(defun t2 (x) (printf "t2 = %d\n" (* x x x)))
	)

	(defun get-name-1() "t1")
	(defun get-name-2() "t2")

	(set x (object-new X))

	(:x (get-name-1) 100) ; must be same as (:x t1 100)
	(:x (get-name-2) 100) ; must be same as (:x t2 100)

## Something to look into..

normal function call
(f arg1 arg2 arg3)
(rcv f arg1 arg2)

## dynamic method invocation???
(:X (f) arg1 arg2)
as long as f returns a symbol, it can also invoke a method??


(defun getX() X) ; ->it must return an object
((getX)->show "hello")

X.Y
 push X
 push_symbol Y
 lookup

(X.Y)
 push X
 push_symbol Y
 lookup
 call 0

X.Y.Z
 push X
 push_symbol Y
 lookup
 push_symbol Z
 lookup
 
 --- if this is within a method, it must become push_instvar
 self.x
  push self
  push symbol x
  lookup




fun f(a, b) 
{
}

fun f(a, b) -> (c, d)
{

}

class X
{
	var x, y, z
	var! printer;

	printer := Printer.new();

	fun! new(a, b)
	{
		return super.new().init(a, b);
	}

	fun init(a, b)
	{
	}

	fun show(a, b)
	{
		Printer.dump(a, b);
	}

}

x := X.new(10, 20);
x.show (40, 50);



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