From 17b346d40a6ac856114dfae365e4f106933d14f9 Mon Sep 17 00:00:00 2001
From: megacz <megacz@xwt.org>
Date: Fri, 30 Jan 2004 07:00:40 +0000
Subject: [PATCH] 2003/06/03 23:21:28

darcs-hash:20040130070040-2ba56-bbd1af048813eabe1fbeae3febc777578e594450.gz
---
 src/org/xwt/js/Parser.java |  276 ++++++++++++++++++++++++--------------------
 1 file changed, 150 insertions(+), 126 deletions(-)

diff --git a/src/org/xwt/js/Parser.java b/src/org/xwt/js/Parser.java
index e99eaa7..c99ff71 100644
--- a/src/org/xwt/js/Parser.java
+++ b/src/org/xwt/js/Parser.java
@@ -104,13 +104,67 @@ public class Parser extends Lexer {
 	// these case arms match the precedence of operators; each arm is a precedence level.
 	switch (tok) {
 
-        case ASSIGN_BITOR: case ASSIGN_BITXOR: case ASSIGN_BITAND: case ASSIGN_LSH:
-	case ASSIGN_RSH: case ASSIGN_URSH: case ASSIGN_ADD: case ASSIGN_SUB: case ASSIGN_MUL: case ASSIGN_DIV: case ASSIGN_MOD:
-	    return new Expr(curLine, ASSIGN, prefix, new Expr(curLine, tok - 1, prefix, parseMaximalExpr(null, precedence[ASSIGN])));
+	case VAR: {
+	    if (prefix != null) { pushBackToken(); return prefix; }
+	    ByteCode b = new ByteCode(curLine);
+	    b.add(b.THIS, NO_ARG);
+	    while(true) {
+		consume(NAME);
+		String name = string;
+		b.add(b.DECLARE, name);
+		if (peekToken() == ASSIGN) {
+		    b.add(b.LITERAL, name);
+		    consume(ASSIGN);
+		    b.add(b.EXPR, parseMaximalExpr());
+		    b.add(b.PUT, NO_ARG);
+		    b.add(b.POP, NO_ARG);
+		}
+		if (peekToken() != COMMA) break;
+		consume(COMMA);
+	    }
+	    return b;
+	}
 
-	    // DONE //
+	case IN: pushBackToken(); return prefix;
+
+	case IF: {
+	    if (prefix != null) { pushBackToken(); return prefix; }
+	    ByteCode b = new ByteCode(curLine);
+	    consume(LP);
+	    b.add(b.EXPR, parseMaximalExpr());
+	    consume(RP);
+	    b.add(b.JF, new Integer(3));
+	    b.add(b.EXPR, parseBlock(false));
+	    b.add(b.JMP, new Integer(2));
+	    if (peekToken() != ELSE) return b.add(b.LITERAL, null);
+	    consume(ELSE);
+	    b.add(b.EXPR, parseBlock(false));
+	    return b;
+	}
 
 	    // FIXME: ugly hack!!
+        case ASSIGN_BITOR: if (tok == ASSIGN_BITOR) tok = BITOR;
+	case ASSIGN_BITXOR: if (tok == ASSIGN_BITXOR) tok = BITXOR;
+	case ASSIGN_BITAND: if (tok == ASSIGN_BITAND) tok = BITAND;
+	case ASSIGN_LSH: if (tok == ASSIGN_LSH) tok = LSH;
+	case ASSIGN_RSH: if (tok == ASSIGN_RSH) tok = RSH;
+	case ASSIGN_URSH: if (tok == ASSIGN_URSH) tok = URSH;
+	case ASSIGN_ADD: if (tok == ASSIGN_ADD) tok = ADD;
+	case ASSIGN_SUB: if (tok == ASSIGN_SUB) tok = SUB;
+	case ASSIGN_MUL: if (tok == ASSIGN_MUL) tok = MUL;
+	case ASSIGN_DIV: if (tok == ASSIGN_DIV) tok = DIV;
+	case ASSIGN_MOD: if (tok == ASSIGN_MOD) tok = MOD;
+	    {
+		ByteCode b = (ByteCode)prefix;
+		b.set(b.size() - 1, b.GET_PRESERVE, new Boolean(true));
+		b.add(b.EXPR, parseMaximalExpr(null, precedence[tok]));
+		b.add(tok, NO_ARG);
+		b.add(b.PUT, NO_ARG);
+		b.add(b.SWAP, NO_ARG);
+		b.add(b.POP, NO_ARG);
+		return b;
+	    }
+
 	case INC: case DEC:
 	    if (prefix == null) {
 		// prefix
@@ -265,9 +319,9 @@ public class Parser extends Lexer {
 		while(true) {
 		    Expr e = parseMaximalExpr();
 		    if (e == null && peekToken() == RB) { consume(RB); return b; }
-		    if (e == null) e = new Expr(curLine, NULL);
 		    b.add(b.LITERAL, new Integer(i++));
-		    b.add(b.EXPR, e);
+		    if (e == null) b.add(b.LITERAL, null);
+		    else b.add(b.EXPR, e);
 		    b.add(b.PUT, NO_ARG);
 		    b.add(b.POP, NO_ARG);
 		    if (peekToken() == RB) { consume(RB); return b; }
@@ -324,69 +378,64 @@ public class Parser extends Lexer {
 	case FUNCTION: {
 	    if (prefix != null) { pushBackToken(); return prefix; }
 	    consume(LP);
-	    ExprList list = new ExprList(curLine, LC);
+	    ByteCode b = new ByteCode(curLine);
+	    int numArgs = 0;
+	    b.add(b.THIS, NO_ARG);
+	    b.add(b.SWAP, NO_ARG);
+	    b.add(b.LITERAL, "arguments");
+	    b.add(b.LITERAL, "arguments");
+	    b.add(b.DECLARE, NO_ARG);
+	    b.add(b.SWAP, NO_ARG);
+	    b.add(b.PUT, NO_ARG);
+	    b.add(b.SWAP, NO_ARG);
+	    b.add(b.POP, NO_ARG);
 	    if (peekToken() == RP) consume(RP);
 	    else while(true) {
-		tok = peekToken();
-		if (tok == COMMA) {
+		if (peekToken() == COMMA) {
 		    consume(COMMA);
-		    list.add(new Expr(curLine, NULL));
 		} else {
 		    consume(NAME);
-		    list.add(new Expr(curLine, NAME, string));
+
+		    // declare the name
+		    b.add(b.LITERAL, string);
+		    b.add(b.DECLARE, NO_ARG);
+
+		    // retrieve it from the arguments array
+		    b.add(b.LITERAL, new Integer(numArgs));
+		    b.add(b.GET_PRESERVE, NO_ARG);
+		    b.add(b.SWAP, NO_ARG);
+		    b.add(b.POP, NO_ARG);
+
+		    // put it to the current scope
+		    b.add(b.THIS, NO_ARG);
+		    b.add(b.SWAP, NO_ARG);
+		    b.add(b.LITERAL, string);
+		    b.add(b.SWAP, NO_ARG);
+		    b.add(b.PUT, NO_ARG);
+
+		    // clean the stack
+		    b.add(b.POP, NO_ARG);
+		    b.add(b.POP, NO_ARG);
+
 		    if (peekToken() == RP) { consume(RP); break; }
 		    consume(COMMA);
 		}
+		numArgs++;
 	    }
-	    return new Expr(curLine, FUNCTION, list, parseBlock(true));
+	    // pop off the arguments array
+	    b.add(b.POP, NO_ARG);
+	    parseBlock(true, b);
+	    return new ByteCode(curLine, b.FUNCTION, b);
 	}
 	    
-	case VAR: {
-	    if (prefix != null) { pushBackToken(); return prefix; }
-	    ByteCode b = new ByteCode(curLine);
-	    b.add(b.THIS, NO_ARG);
-	    while(true) {
-		consume(NAME);
-		String name = string;
-		b.add(b.DECLARE, name);
-		if (peekToken() == ASSIGN) {
-		    b.add(b.LITERAL, name);
-		    consume(ASSIGN);
-		    b.add(b.EXPR, parseMaximalExpr());
-		    b.add(b.PUT, NO_ARG);
-		    b.add(b.POP, NO_ARG);
-		}
-		if (peekToken() != COMMA) break;
-		consume(COMMA);
-	    }
-	    return b;
-	}
-
-	case IN: pushBackToken(); return prefix;
-
-	case IF: {
-	    if (prefix != null) { pushBackToken(); return prefix; }
-	    ByteCode b = new ByteCode(curLine);
-	    consume(LP);
-	    b.add(b.EXPR, parseMaximalExpr());
-	    consume(RP);
-	    b.add(b.JF, new Integer(3));
-	    b.add(b.EXPR, parseBlock(false));
-	    b.add(b.JMP, new Integer(2));
-	    if (peekToken() != ELSE) return b.add(b.LITERAL, null);
-	    consume(ELSE);
-	    b.add(b.EXPR, parseBlock(false));
-	    return b;
-	}
-
 	    // Needs break //
 
 	case SWITCH: {
 	    if (prefix != null) { pushBackToken(); return prefix; }
-	    if (getToken() != LP) throw new ParserException("expected left paren");
+	    consume(LP);
 	    Expr switchExpr = parseMaximalExpr();
-	    if (getToken() != RP) throw new ParserException("expected left paren");
-	    if (getToken() != LC) throw new ParserException("expected left brace");
+	    consume(RP);
+	    consume(LC);
 	    ExprList toplevel = new ExprList(curLine, LC);
 	    while(true) {
 		tok = getToken();
@@ -519,6 +568,7 @@ public class Parser extends Lexer {
 	public static final byte DECLARE = -6;     // < name >                      -- declare <name> in the current scope
 	public static final byte THIS = -7;        //                               -- push the topmost non-transparent scope onto the stack
 	public static final byte GET = -8;         //                               -- get stack[0] from stack[1]
+	public static final byte GET_PRESERVE = -80;         //                               -- get stack[0] from stack[1]
 	public static final byte PUT = -9;         //                               -- put stack[1] to key stack[0] on stack[2]; leaves object on the stack
 	public static final byte THROW = -10;      //                               -- throw topmost element
 	public static final byte RETURN = -11;     //                               -- return the topmost value on the stack
@@ -562,7 +612,7 @@ public class Parser extends Lexer {
 	public Object eval(final JS.Scope s) throws ControlTransferException, JS.Exn {
 	    return eval(s, new Parser.Thread());
 	}
-	public Object eval(JS.Scope s, Parser.Thread t) throws ControlTransferException {
+	public Object eval(final JS.Scope s, Parser.Thread t) throws ControlTransferException {
 	    for(int i=0; i<size; i++)
 		switch(op[i]) {
 		case arithmetic: break;
@@ -595,6 +645,13 @@ public class Parser extends Lexer {
 		    t.push(doGet(o, v));
 		    break;
 		}
+		case GET_PRESERVE: {
+		    Object v = t.pop();
+		    Object o = t.peek();
+		    t.push(v);
+		    t.push(doGet(o, v));
+		    break;
+		}
 		case NOP: break;
 		    
 		case EXPR: t.push(((Expr)arg[i]).eval(s)); break;
@@ -610,7 +667,40 @@ public class Parser extends Lexer {
 		    t.push(f.call(arguments));
 		    break;
 
-		case FUNCTION: break;
+		case FUNCTION: {
+		    final ByteCode myBytes = (ByteCode)arg[i];
+		    t.push(new JS.Function() {
+			public String toString() { return sourceName + ":" + line; }
+			public String getSourceName() throws JS.Exn { return sourceName; }
+			public Object _call(final JS.Array args) throws JS.Exn {
+			    Function save = JS.getCurrentFunction();
+			    JS.currentFunction.put(java.lang.Thread.currentThread(), this);
+			    JS.Scope scope = new JS.Scope(s) {
+				    // FIXME
+				    public String getSourceName() { return sourceName; }
+				    public Object get(Object key) throws JS.Exn {
+					if (key.equals("trapee")) return org.xwt.Trap.currentTrapee();
+					else if (key.equals("cascade")) return org.xwt.Trap.cascadeFunction;
+					return super.get(key);
+				    }
+				};
+			    Parser.Thread t0 = new Parser.Thread();
+			    t0.push(args);
+			    try {
+				return myBytes.eval(scope, t0);
+			    } catch (ReturnException r) {
+				return r.retval;
+			    } catch (ControlTransferException c) {
+				throw new EvaluatorException("error, ControlTransferException tried to leave a function: " + c);
+			    } finally {
+				if (save == null) JS.currentFunction.remove(java.lang.Thread.currentThread());
+				else JS.currentFunction.put(java.lang.Thread.currentThread(), save);
+			    }
+			}
+		    });
+		    break;
+		}
+
 		case RETURN: break;
 		case TRY: break;
 		case INSTANCEOF: break;
@@ -728,7 +818,7 @@ public class Parser extends Lexer {
 			    if (args.length() != 1) return null;
 			    return new Integer(((String)o).indexOf(args.elementAt(0).toString()));
 			} };
-		throw new Error("Not Implemented: properties on String objects");
+		throw new Error("Not Implemented: propery " + v + " on String objects");
 	    } else if (o instanceof Boolean) {
 		throw new Error("Not Implemented: properties on Boolean objects");
 	    } else if (o instanceof Number) {
@@ -821,7 +911,8 @@ public class Parser extends Lexer {
     }
     
     /** a block is either a single statement or a list of statements surrounded by curly braces; all expressions are also statements */
-    public Expr parseBlock(boolean requireBraces) throws IOException {
+    public Expr parseBlock(boolean requireBraces) throws IOException { return parseBlock(requireBraces, null); }
+    public Expr parseBlock(boolean requireBraces, ByteCode b) throws IOException {
 	Expr smt = null;
 	int tok = peekToken();
 	if (tok == -1) return null;
@@ -830,7 +921,7 @@ public class Parser extends Lexer {
 	if (braced) consume(LC);
 	int curLine = line;
 	ByteCode ret = new ByteCode(curLine);
-	ByteCode block = new ByteCode(curLine);
+	ByteCode block = b == null ? new ByteCode(curLine) : b;
 	block.add(ret.LITERAL, Boolean.TRUE);
 	ret.add(block.SCOPE, block);
 	while(true) {
@@ -950,6 +1041,7 @@ public class Parser extends Lexer {
 	public Object eval(final JS.Scope s) throws ControlTransferException, JS.Exn {
 	    switch(code) {
 
+	    case Lexer.NULL: return null;
 	    case Lexer.TYPEOF: {
 		Object o = left.eval(s);
 		if (o == null) return "null";
@@ -961,38 +1053,7 @@ public class Parser extends Lexer {
 		throw new EvaluatorException("typeof " + o.getClass().getName() + " unknown");
 	    }
 
-	    case Lexer.NUMBER: return number;
-	    case Lexer.STRING: return string;
-
-	    case Lexer.ASSIGN: {
-		Object v = (code == Lexer.ASSIGN) ? right.eval(s) : new Double(toDouble(left.eval(s)) + (code == Lexer.INC ? 1 : -1));
-		if (left.code == Lexer.DOT) {
-		    Object o = left.left.eval(s);
-		    if (o instanceof String) {
-			throw new EvaluatorException("can't set properties on a String");
-		    } else if (o instanceof Number) {
-			throw new EvaluatorException("can't set properties on a Number");
-		    } else if (o instanceof Boolean) {
-			throw new EvaluatorException("can't set properties on a Boolean");
-		    } else {
-			JS target = (JS)o;
-			if (target == null) throw new JS.Exn(new EvaluatorException("attempted to put to the null value"));
-			target.put(left.right.eval(s), v);
-			return v;
-		    }
-		} else {
-		    s.put(left.string, v);
-		    return v;
-		}
-	    }
-
-	    case Lexer.NULL: return null;
-	    case Lexer.FALSE: return Boolean.FALSE;
-	    case Lexer.TRUE: return Boolean.TRUE;
-	    case Lexer.ASSERT: if (!toBoolean(left.eval(s))) throw new EvaluatorException("assertion failed");
 	    case Lexer.THROW: throw new JS.Exn(left.eval(s));
-	    case Lexer.NAME: return s.get(string);
-	    case Lexer.THIS: return s.isTransparent() ? s : this.eval(s.getParentScope());
 
 	    case Lexer.TRY: {
 		boolean safeToExit = false;
@@ -1019,43 +1080,6 @@ public class Parser extends Lexer {
 		return null;
 	    }
 
-	    case Lexer.FUNCTION:
-		return new JS.Function() {
-			public String toString() { return right.sourceName + ":" + right.line; }
-			public String getSourceName() throws JS.Exn { return right.sourceName; }
-			public Object _call(final JS.Array args) throws JS.Exn {
-			    Function save = JS.getCurrentFunction();
-			    JS.currentFunction.put(java.lang.Thread.currentThread(), this);
-			    JS.Scope scope = new JS.Scope(s) {
-				    // FIXME
-				    public String getSourceName() { return sourceName; }
-				    public Object get(Object key) throws JS.Exn {
-					if (key.equals("trapee")) return org.xwt.Trap.currentTrapee();
-					else if (key.equals("cascade")) return org.xwt.Trap.cascadeFunction;
-					else if (key.equals("arguments")) return args;
-					return super.get(key);
-				    }
-				};
-			    int i = 0;
-			    ExprList list = (ExprList)left;
-			    for(i=0; i<list.size(); i++) {
-				scope.declare(list.elementAt(i).string);
-				scope.put(list.elementAt(i).string, args.get(new Integer(i)));
-			    }
-			    try {
-				return right.eval(scope);
-			    } catch (ReturnException r) {
-				return r.retval;
-			    } catch (ControlTransferException c) {
-				throw new EvaluatorException("error, ControlTransferException tried to leave a function: "
-							     + c);
-			    } finally {
-				if (save == null) JS.currentFunction.remove(java.lang.Thread.currentThread());
-				else JS.currentFunction.put(java.lang.Thread.currentThread(), save);
-			    }
-			}
-		    };
-		
 	    case Lexer.FOR:
 		Object[] keys = ((JS)left.right.eval(s)).keys();
 		for(int i=0; i<keys.length; i++) {
-- 
1.7.10.4