36c517dfc4 2010-11-23        kinaba: /**
36c517dfc4 2010-11-23        kinaba:  * Authors: k.inaba
36c517dfc4 2010-11-23        kinaba:  * License: NYSL 0.9982 (http://www.kmonos.net/nysl/)
36c517dfc4 2010-11-23        kinaba:  *
36c517dfc4 2010-11-23        kinaba:  * Read-Eval-Print-Loop
36c517dfc4 2010-11-23        kinaba:  */
36c517dfc4 2010-11-23        kinaba: module polemy.repl;
36c517dfc4 2010-11-23        kinaba: import polemy.failure;
36c517dfc4 2010-11-23        kinaba: import polemy.layer;
36c517dfc4 2010-11-23        kinaba: import polemy.eval;
36c517dfc4 2010-11-23        kinaba: import polemy.runtime;
36c517dfc4 2010-11-23        kinaba: import polemy.value;
36c517dfc4 2010-11-23        kinaba: import polemy.valueconv;
36c517dfc4 2010-11-23        kinaba: import std.stdio;
36c517dfc4 2010-11-23        kinaba: import std.string;
36c517dfc4 2010-11-23        kinaba: 
36c517dfc4 2010-11-23        kinaba: enum VersionNoMajor = 0; /// Version Number
36c517dfc4 2010-11-23        kinaba: enum VersionNoMinor = 1; /// Version Number
36c517dfc4 2010-11-23        kinaba: enum VersionNoRev   = 0; /// Version Number
36c517dfc4 2010-11-23        kinaba: 
36c517dfc4 2010-11-23        kinaba: /// Read-Eval-Print-Loop
36c517dfc4 2010-11-23        kinaba: 
36c517dfc4 2010-11-23        kinaba: class REPL
36c517dfc4 2010-11-23        kinaba: {
36c517dfc4 2010-11-23        kinaba: 	/// Load the prelude environment
36c517dfc4 2010-11-23        kinaba: 	this(string[] args)
36c517dfc4 2010-11-23        kinaba: 	{
36c517dfc4 2010-11-23        kinaba: 		ev = new Evaluator;
36c517dfc4 2010-11-23        kinaba: 		ev.globalContext.set("argv", ValueLayer, d2polemy(args));
36c517dfc4 2010-11-23        kinaba: 		enrollRuntimeLibrary(ev);
36c517dfc4 2010-11-23        kinaba: 	}
36c517dfc4 2010-11-23        kinaba: 
36c517dfc4 2010-11-23        kinaba: 	/// Print the version number etc.
36c517dfc4 2010-11-23        kinaba: 	void greet()
36c517dfc4 2010-11-23        kinaba: 	{
36c517dfc4 2010-11-23        kinaba: 		writefln("Welcome to Polemy %d.%d.%d", VersionNoMajor, VersionNoMinor, VersionNoRev);
36c517dfc4 2010-11-23        kinaba: 	}
36c517dfc4 2010-11-23        kinaba: 
36c517dfc4 2010-11-23        kinaba: 	/// Run one file on the global scope
36c517dfc4 2010-11-23        kinaba: 	void runFile(string filename)
36c517dfc4 2010-11-23        kinaba: 	{
36c517dfc4 2010-11-23        kinaba: 		ev.evalFile(filename);
36c517dfc4 2010-11-23        kinaba: 	}
36c517dfc4 2010-11-23        kinaba: 
36c517dfc4 2010-11-23        kinaba: 	/// Repeat the singleInteraction
36c517dfc4 2010-11-23        kinaba: 	void replLoop()
36c517dfc4 2010-11-23        kinaba: 	{
36c517dfc4 2010-11-23        kinaba: 		while( singleInteraction() ) {}
36c517dfc4 2010-11-23        kinaba: 	}
36c517dfc4 2010-11-23        kinaba: 
36c517dfc4 2010-11-23        kinaba: 	/// Read one line from stdin, and do some reaction
36c517dfc4 2010-11-23        kinaba: 	bool singleInteraction()
36c517dfc4 2010-11-23        kinaba: 	{
36c517dfc4 2010-11-23        kinaba: 		writef(">> ", lineno);
36c517dfc4 2010-11-23        kinaba: 		string line = readln();
36c517dfc4 2010-11-23        kinaba: 		if( line.startsWith("exit") || line.startsWith("quit") )
36c517dfc4 2010-11-23        kinaba: 			return false;
36c517dfc4 2010-11-23        kinaba: 		try {
36c517dfc4 2010-11-23        kinaba: 			if( tryRun(line) )
36c517dfc4 2010-11-23        kinaba: 				writeln(lastVal);
36c517dfc4 2010-11-23        kinaba: 		} catch(Throwable e) {
36c517dfc4 2010-11-23        kinaba: 			writeln(e);
36c517dfc4 2010-11-23        kinaba: 		}
36c517dfc4 2010-11-23        kinaba: 		return true;
36c517dfc4 2010-11-23        kinaba: 	}
36c517dfc4 2010-11-23        kinaba: 
36c517dfc4 2010-11-23        kinaba: private:
36c517dfc4 2010-11-23        kinaba: 	Evaluator ev;
36c517dfc4 2010-11-23        kinaba: 	Table ctx;
36c517dfc4 2010-11-23        kinaba: 	string buf;
36c517dfc4 2010-11-23        kinaba: 	Value  lastVal;
36c517dfc4 2010-11-23        kinaba: 	int lineno = 1;
36c517dfc4 2010-11-23        kinaba: 	int nextlineno = 1;
36c517dfc4 2010-11-23        kinaba: 
36c517dfc4 2010-11-23        kinaba: 	bool tryRun( string s )
36c517dfc4 2010-11-23        kinaba: 	{
36c517dfc4 2010-11-23        kinaba: 		scope(failure)
36c517dfc4 2010-11-23        kinaba: 			{ buf = ""; lineno = nextlineno; }
36c517dfc4 2010-11-23        kinaba: 
36c517dfc4 2010-11-23        kinaba: 		buf ~= s;
36c517dfc4 2010-11-23        kinaba: 		nextlineno ++;
36c517dfc4 2010-11-23        kinaba: 		try
36c517dfc4 2010-11-23        kinaba: 			{ lastVal = ev.evalString(buf, "<REPL>", lineno); }
36c517dfc4 2010-11-23        kinaba: 		catch( UnexpectedEOF )
36c517dfc4 2010-11-23        kinaba: 			{ return false; } // wait
36c517dfc4 2010-11-23        kinaba: 		buf = "";
36c517dfc4 2010-11-23        kinaba: 		lineno = nextlineno;
36c517dfc4 2010-11-23        kinaba: 		return true;
36c517dfc4 2010-11-23        kinaba: 	}
36c517dfc4 2010-11-23        kinaba: }