My scripting language - any suggestions?

Hi!


I've been writing my own scripting language for 6 months (with some
small breaks). I wrote the lexer, parser (similar to recursive
descent, but extended; LL grammar) and now I'm writing the
interpreter. The syntax is similar to C/C++ and the language is mostly
influenced by PHP and Lua. Sample code:


[code]
// a comment


class Child extends Parent
{
        public x;
        protected y;
        private z;


        static public function Run()
        {
                /*
                        other stuff
                */
                super.Run();
        }
}


t = [ 1, 2, 3 ]; // array, like array() in PHP
a =
[
        x = t,
        'y' = 15,
        'z' = 'to jest co6',
];


foreach( a as k,v ): petla
{
        if( is_array(v) )
                foreach( v as v2 )
                        print(v2);
        else
                print(v);
}


for( i = 0; i < 5; ++i )
        print(i);


k = new Child a;
[/code]


Yeah. It's just like PHP, but without the '$'. One significant
difference will be that you can do


[code]
t.DoSth();
[/code]


instead of


[code]
array_DoSth(t);
[/code]


etc. Upgraded PHP? Something like that... Anyway I'm having some
difficulties. One small decision, should variables should be declared:


[code]
var a = 5; // or
local a = 5; // like in lua or unreal script, or
global a = 5; // declaration of a global variable in given scope, not
like referencing global variables in PHP, or
a = 5;
[/code]


And the second problem. What kind of scope to implement. In PHP you
have either global or local (function) scope. So writing:


[code]
if( variable )
{
        a = 5;
}


print(a);
[/code]


gives the result '5'. Something like this would mean a compiler error
in C++. But I'm willing to implement it as per block (like in C/C++)
scope. Anyone seeing any prons/cons? The interpreter is a simple AST
walking class, but when some problems are fixed I will replace it with
a bytecode VM (like in Lua). And as for the VM itself... stack or
register based? :)


That's all of my questions (doubts) so far. Thanks for your help. But
if you're just gonna write 'use (f)lex/yacc/whatever' or 'why another
language, python/ruby/php/whatever is great' please don't :P I'm not
even going to read it. Everyone else is invited to this discussion.
Help me build my first scripting language! :)

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