[antlr-interest] Example of a scripting language?

[Rick Mann]

I'm trying to build a very simple scripting language that has a C++/ 
Java-like syntax for defining simple and aggregate types. I have a  
GUI application that allows the user to type in commands in the  
language, but I'm not sure how to wire in the generated parser.

I figure I will call the parser multiple times as the user enters  
lines, but I have two types of state to keep track of.

One is the parser's actual state. It would be easiest for me to feed  
the parser a line at a time, as the user types it, but I'm not sure  
how to do this. One line may not represent a completely parseable  
(sp?) set of input (i.e., a statement may span multiple lines).

The other state is the result of multiple input statements. I think I  
understand how to maintain this state; it's simply up to the  
generated code to put it somewhere it can be kept.

Examples (">> " is my system's prompt):


 >> UInt32 foo = 123;		//  UInt32 is a pre-defined type reprsenting a  
32-bit unsigned integer

No output as a result of this parser input.

 >> send foo;

Sent 4 bytes			// System's output into interpreter window.
 >>

 >> struct FooT {

No output, the call to the parser has returned, and it needs more, so  
the prompt is displayed again:

 >> UInt32 field1;

No output, but more inptu is needed:

 >> };

No output, but now a new type is defined, "FooT".

 >> FooT myFoo;

No output, but FooT is instantiated as myFoo.

 >> myFoo.field1 = 123;

myFoo.field1 gets assigned a value.

Etc. This seems like it should be straightforward, but most of the  
examples show complete translations. Can someone point me in the  
right direction? Thanks!

-- 
Rick