From: Jakub Travnik <j.travnik@...>
Date: 2002-04-19T21:28:49+09:00
Subject: Re: Experimental language jtpl

Sean Middleditch wrote:
 >
 > But those are the most fun languages to hack on.  ^,^

yes :-)

> Could you explain that better?  I mean, in terms a moron like me can
> understand?  ~,^  I'm curious about that feature.  It sounds almost
> something like Scriptix uses, although the "variable" is not named or
> accessible from within the function (but it's there.)  Do you just maen
> you have that, but the variable can be accessed and manipulated by the
> function before actually returning?

note: if you are interrested in this stuff, see examples inside jtpl source

Ok, function is written in following way:
----------------------
{ |param1, param2|
  var variable1,variable2; -- note: variables are untyped unlike values
  statement1;
  statement2;
  return(4); -- this is ordinary function/continuation call
}
----------------------


this function is anonymous it but can be assigned to variable i.e:
----------------------
var double;
double={|x| return(2*2);};
writenum(double(3)); -- writes 6
----------------------


Calling function and calling continuation is
same except that continuation have always only one argument.

now program that uses continuations:
----------------------
var f,cont,counter; -- variable declaration

f={
         cont=return;  -- set cont to continuation of this function
                       -- return is like ordinary variable it can be read or written
         return(100);  -- return 100
};

counter=0;            -- set counter to zero
writenum(10+f()+1000);-- call b and write result of addition

counter=counter+1;    -- increase counter

if(counter<4)         -- loop limited number of times
         cont(d);      -- reuse continuation in cont,
                       -- this will restart computation inside addition/writenum above
end;
----------------------
source above will print numbers: 1110, 1011, 1012, 1013


I hope this helps.

Happy hacking,

Jakub Travnik
jabber://jtra@jabber.com