Nasal Interpreter
Nasal script language
Nasal is a script language that used in FlightGear.
There is a Nasal console in FlightGear but sometimes it is not so easy for every developer to use.
So this is an interpreter for Nasal written by C++.
The interpreter is still in development.Anyone who interested in this could also join us!
Lexical Analysis
What do it's outputs look like?
( identifier | engineTimer )
( operator | . )
( identifier | start )
( operator | ; )
( reserve word | print )
( operator | ( )
( string | Engine started )
( operator | ) )
( operator | ; )
This is what it outputs.
And the flow chart of lexer is here:
Push down automata
After many times of failure,i finally try to use PDA to do the parse work.
But something occurred,so i finally didn't make it.However you can still see this LL(1) and LR(0) parser in version 0.7 & 0.9 .
Parser
The parser can recognize some basic elements in resource program.
In version 1.1 you can use the fully-functional parser.
But there are still some differences such as:
(var a,b,c)=(1,2,3);
var (r,g,b)=color;
(a,b)=(b,a);
etc. cannot be recognized.
And each statement must have a ';' after it or you will be informed with 'error: expect a ';'' .
Calculator
You can try a calculator in version 0.17~0.19 !
Abstract Syntax Tree
In version 1.2 the ast has been completed.
But there are still some bugs inside.
Balloon script
Balloon is created for experiment.
It is a subset of Nasal and the parser is stricter than Nasal parser.
Explore the usage of balloon and enjoy yourself! XD