- first cut at building and printing AST

R=r
OCL=15675
CL=15675

usr/gri/pretty/Makefile

@@ -9,16 +9,16 @@ pretty: pretty.6
 	$(L) -o pretty pretty.6
 
 test: pretty
-	pretty *.go
-	pretty ../gosrc/*.go
-	pretty $(GOROOT)/test/sieve.go
-	pretty $(GOROOT)/src/pkg/*.go
-	pretty $(GOROOT)/src/lib/flag.go
-	pretty $(GOROOT)/src/lib/fmt.go
-	pretty $(GOROOT)/src/lib/rand.go
-	pretty $(GOROOT)/src/lib/math/*.go
-	pretty $(GOROOT)/src/lib/container/*.go
-	pretty $(GOROOT)/src/syscall/*.go
+	pretty -s *.go
+	pretty -s ../gosrc/*.go
+	pretty -s $(GOROOT)/test/sieve.go
+	pretty -s $(GOROOT)/src/pkg/*.go
+	pretty -s $(GOROOT)/src/lib/flag.go
+	pretty -s $(GOROOT)/src/lib/fmt.go
+	pretty -s $(GOROOT)/src/lib/rand.go
+	pretty -s $(GOROOT)/src/lib/math/*.go
+	pretty -s $(GOROOT)/src/lib/container/*.go
+	pretty -s $(GOROOT)/src/syscall/*.go
 	echo "DONE"
 
 install: pretty
@@ -29,7 +29,7 @@ clean:
 
 pretty.6:	parser.6 printer.6 platform.6 scanner.6
 
-parser.6:	ast.6 scanner.6 utils.6
+parser.6:	ast.6 scanner.6 utils.6 printer.6
 
 scanner.6:	utils.6 platform.6
 

usr/gri/pretty/ast.go

@@ -4,36 +4,114 @@
 
 package AST;
 
+// ----------------------------------------------------------------------------
+// Lists
+
+export type Element interface {}
+
+
+export type List struct {
+	a *[] Element
+}
+
+
+func (p *List) len() int {
+	return len(p.a);
+}
+
+
+func (p *List) at(i int) Element {
+	return p.a[i];
+}
+
+
+func (p *List) Add (x Element) {
+	a := p.a;
+	n := len(a);
+
+	if n == cap(a) {
+		b := new([] interface {}, 2*n);
+		for i := 0; i < n; i++ {
+			b[i] = a[i];
+		}
+		a = b;
+	}
+
+	a = a[0 : n + 1];
+	a[n] = x;
+	p.a = a;
+}
+
+
+export func NewList() *List {
+	p := new(List);
+	p.a = new([] interface {}, 10);
+	return p;
+}
+
+
+// ----------------------------------------------------------------------------
+// Expressions
 
 export type Expr interface {
-       pos() int;
-       print();
 }
 
 
-export type Stat interface {
-       pos() int;
-       print();
+export type Selector struct {
+	pos int;
+	x Expr;
+	field string;
 }
 
 
-// ---------------------------------------------------------------------
-// Concrete nodes
+export type Index struct {
+	pos int;
+	x Expr;
+	index Expr;
+}
+
 
-export type Ident struct {
-       pos_ int;
-       val_ string;
+export type Pair struct {
+	pos int;
+	x, y Expr;
 }
 
 
-func (p *Ident) pos() int {
-     return p.pos_;
+export type Binary struct {
+	pos int;
+	tok int;
+	x, y Expr;
 }
 
 
-func (p *Ident) print() {
-     print("x");  // TODO fix this
+export type Unary struct {
+	pos int;
+	tok int;
+	x Expr;
+}
+
+
+export type Literal struct {
+	pos int;
+	tok int;
+	val string;
+}
+
+
+// ----------------------------------------------------------------------------
+// Statements
+
+
+// ----------------------------------------------------------------------------
+// Visitor
+
+export type Visitor interface {
+  DoBinary(x *Binary);
+  //DoUnary(x *Unary);
+  //DoLiteral(x *Literal);
 }
 
 
-// TODO: complete this
+func (x *Binary)  Visit(v Visitor)  { v.DoBinary(x); }
+//func (x *Unary)   Visit(v Visitor)  { v.DoUnary(x); }
+//func (x *Literal) Visit(v Visitor)  { v.DoLiteral(x); }

usr/gri/pretty/parser.go

@@ -6,8 +6,11 @@ package Parser
 
 import Scanner "scanner"
 import AST "ast"
+import Printer "printer"
+
 
 export type Parser struct {
+	silent bool;
 	verbose bool;
 	indent uint;
 	scanner *Scanner.Scanner;
@@ -65,7 +68,8 @@ func (P *Parser) Next() {
 }
 
 
-func (P *Parser) Open(verbose bool, scanner *Scanner.Scanner, tokchan *<-chan *Scanner.Token) {
+func (P *Parser) Open(silent, verbose bool, scanner *Scanner.Scanner, tokchan *<-chan *Scanner.Token) {
+	P.silent = silent;
 	P.verbose = verbose;
 	P.indent = 0;
 	P.scanner = scanner;
@@ -115,16 +119,16 @@ func (P *Parser) TryStatement() bool;
 func (P *Parser) ParseDeclaration();
 
 
-func (P *Parser) ParseIdent() *AST.Ident {
+func (P *Parser) ParseIdent() *AST.Literal {
 	P.Trace("Ident");
 
-	ident := new(AST.Ident);
-	ident.pos_, ident.val_ = P.pos, "";
+	ident := new(AST.Literal);
+	ident.pos, ident.tok, ident.val = P.pos, Scanner.IDENT, "";
 	if P.tok == Scanner.IDENT {
-		ident.val_ = P.val;
+		ident.val = P.val;
 		if P.verbose {
 			P.PrintIndent();
-			print("Ident = \"", ident.val_, "\"\n");
+			print("Ident = \"", ident.val, "\"\n");
 		}
 		P.Next();
 	} else {
@@ -152,19 +156,26 @@ func (P *Parser) ParseIdentList() int {
 }
 
 
-func (P *Parser) ParseQualifiedIdent(ident *AST.Ident) AST.Expr {
+func (P *Parser) ParseQualifiedIdent(ident *AST.Literal) AST.Expr {
 	P.Trace("QualifiedIdent");
 
 	if ident == nil {
 		ident = P.ParseIdent();
 	}
+
+	var x AST.Expr = ident;
+	
 	if P.tok == Scanner.PERIOD {
 	   	 P.Next();
-		 ident = P.ParseIdent();
+		 ident2 := P.ParseIdent();
+		 
+		 z := new(AST.Selector);
+		 z.pos, z.x, z.field = ident.pos, ident, ident2.val;
+		 x = z;
 	}
 	
 	P.Ecart();
-	return ident;
+	return x;
 }
 
 
@@ -471,16 +482,18 @@ func (P *Parser) ParseBlock() {
 // ----------------------------------------------------------------------------
 // Expressions
 
-func (P *Parser) ParseExpressionList() {
+func (P *Parser) ParseExpressionList() *AST.List {
 	P.Trace("ExpressionList");
 
-	P.ParseExpression();
+	p := AST.NewList();
+	p.Add(P.ParseExpression());
 	for P.tok == Scanner.COMMA {
 		P.Next();
-		P.ParseExpression();
+		p.Add(P.ParseExpression());
 	}
 	
 	P.Ecart();
+	return p;
 }
 
 
@@ -497,26 +510,33 @@ func (P *Parser) ParseFunctionLit() AST.Expr {
 }
 
 
-func (P *Parser) ParseExpressionPair() {
+func (P *Parser) ParseExpressionPair() AST.Expr {
 	P.Trace("ExpressionPair");
 
-	P.ParseExpression();
+	x := P.ParseExpression();
+	pos := P.pos;
 	P.Expect(Scanner.COLON);
-	P.ParseExpression();
+	y := P.ParseExpression();
+	
+	z := new(AST.Pair);
+	z.pos, z.x, z.y = pos, x, y;
 	
 	P.Ecart();
+	return z;
 }
 
 
-func (P *Parser) ParseExpressionPairList() {
+func (P *Parser) ParseExpressionPairList() *AST.List {
 	P.Trace("ExpressionPairList");
 
-	P.ParseExpressionPair();
+	p := AST.NewList();
+	p.Add(P.ParseExpressionPair());
 	for P.tok == Scanner.COMMA {
-		P.ParseExpressionPair();
+		p.Add(P.ParseExpressionPair());
 	}
 	
 	P.Ecart();
+	return p;
 }
 
 
@@ -546,12 +566,11 @@ func (P *Parser) ParseCompositeLit() AST.Expr {
 	P.Expect(Scanner.RBRACE);
 
 	P.Ecart();
-	var x AST.Expr;
-	return x;
+	return nil;
 }
 
 
-func (P *Parser) ParseOperand(ident *AST.Ident) AST.Expr {
+func (P *Parser) ParseOperand(ident *AST.Literal) AST.Expr {
 	P.Trace("Operand");
 
 	if ident == nil && P.tok == Scanner.IDENT {
@@ -559,39 +578,37 @@ func (P *Parser) ParseOperand(ident *AST.Ident) AST.Expr {
 		ident = P.ParseIdent();
 	}
 
-	var x AST.Expr;
+	var z AST.Expr;
 
 	if ident != nil {
-		// we have an identifier
+		z = ident;
 
 	} else {
 	
 		switch P.tok {
 		case Scanner.LPAREN:
 			P.Next();
-			x = P.ParseExpression();
+			z = P.ParseExpression();
 			P.Expect(Scanner.RPAREN);
 
-		case Scanner.INT:
-			P.Next();
-
-		case Scanner.FLOAT:
-			P.Next();
-
-		case Scanner.STRING:
+		case Scanner.INT, Scanner.FLOAT, Scanner.STRING:
+			x := new(AST.Literal);
+			x.pos, x.tok, x.val = P.pos, P.tok, P.val;
+			z = x;
 			P.Next();
 
 		case Scanner.FUNC:
-			P.ParseFunctionLit();
+			z = P.ParseFunctionLit();
 			
 		case Scanner.HASH:
 			P.Next();
 			P.ParseType();
 			P.ParseCompositeLit();
+			z = nil;
 
 		default:
 			if P.tok != Scanner.IDENT && P.TryType() {
-				P.ParseCompositeLit();
+				z = P.ParseCompositeLit();
 			} else {
 				P.Error(P.pos, "operand expected");
 				P.Next();  // make progress
@@ -601,18 +618,23 @@ func (P *Parser) ParseOperand(ident *AST.Ident) AST.Expr {
 	}
 
 	P.Ecart();
-	return x;
+	return z;
 }
 
 
 func (P *Parser) ParseSelectorOrTypeGuard(x AST.Expr) AST.Expr {
 	P.Trace("SelectorOrTypeGuard");
 
-	P.Expect(Scanner.PERIOD);
 	pos := P.pos;
+	P.Expect(Scanner.PERIOD);
+	
+	if P.tok == Scanner.IDENT {
+		ident := P.ParseIdent();
+		
+		z := new(AST.Selector);
+		z.pos, z.x, z.field = pos, x, ident.val;
+		x = z;
 		
-	if P.tok >= Scanner.IDENT {
-		P.ParseIdent();
 	} else {
 		P.Expect(Scanner.LPAREN);
 		P.ParseType();
@@ -627,16 +649,21 @@ func (P *Parser) ParseSelectorOrTypeGuard(x AST.Expr) AST.Expr {
 func (P *Parser) ParseIndexOrSlice(x AST.Expr) AST.Expr {
 	P.Trace("IndexOrSlice");
 	
+	pos := P.pos;
 	P.Expect(Scanner.LBRACK);
 	i := P.ParseExpression();
 	if P.tok == Scanner.COLON {
 		P.Next();
 		j := P.ParseExpression();
+		// TODO: handle this case
 	}
 	P.Expect(Scanner.RBRACK);
 
+	z := new(AST.Index);
+	z.pos, z.x, z.index = pos, x, i;
+	
 	P.Ecart();
-	return x;
+	return z;
 }
 
 
@@ -668,20 +695,19 @@ func (P *Parser) ParseCall(x AST.Expr) AST.Expr {
 }
 
 
-func (P *Parser) ParsePrimaryExpr(ident *AST.Ident) AST.Expr {
+func (P *Parser) ParsePrimaryExpr(ident *AST.Literal) AST.Expr {
 	P.Trace("PrimaryExpr");
 	
 	x := P.ParseOperand(ident);
-	for {
+	L: for {
 		switch P.tok {
 		case Scanner.PERIOD: x = P.ParseSelectorOrTypeGuard(x);
 		case Scanner.LBRACK: x = P.ParseIndexOrSlice(x);
 		case Scanner.LPAREN: x = P.ParseCall(x);
-		default: goto exit;
+		default: break L;
 		}
 	}
 
-exit:
 	P.Ecart();
 	return x;
 }
@@ -690,23 +716,26 @@ exit:
 func (P *Parser) ParseUnaryExpr() AST.Expr {
 	P.Trace("UnaryExpr");
 	
+	var x AST.Expr;
 	switch P.tok {
-	case Scanner.ADD: fallthrough;
-	case Scanner.SUB: fallthrough;
-	case Scanner.NOT: fallthrough;
-	case Scanner.XOR: fallthrough;
-	case Scanner.MUL: fallthrough;
-	case Scanner.ARROW: fallthrough;
-	case Scanner.AND:
+	case
+		Scanner.ADD, Scanner.SUB,
+		Scanner.NOT, Scanner.XOR,
+		Scanner.MUL, Scanner.ARROW,
+		Scanner.AND:
+			pos, tok := P.pos, P.tok;
 			P.Next();
-		x := P.ParseUnaryExpr();
-		P.Ecart();
-		return x;  // TODO fix this
+			y := P.ParseUnaryExpr();
+
+			x := new(AST.Unary);
+			x.pos, x.tok, x.x = pos, tok, y;
+			
+		default:
+			x = P.ParsePrimaryExpr(nil);
 	}
 	
-	x := P.ParsePrimaryExpr(nil);
 	P.Ecart();
-	return x;  // TODO fix this
+	return x;
 }
 
 
@@ -730,7 +759,7 @@ func Precedence(tok int) int {
 }
 
 
-func (P *Parser) ParseBinaryExpr(ident *AST.Ident, prec1 int) AST.Expr {
+func (P *Parser) ParseBinaryExpr(ident *AST.Literal, prec1 int) AST.Expr {
 	P.Trace("BinaryExpr");
 	
 	var x AST.Expr;
@@ -742,8 +771,13 @@ func (P *Parser) ParseBinaryExpr(ident *AST.Ident, prec1 int) AST.Expr {
 
 	for prec := Precedence(P.tok); prec >= prec1; prec-- {
 		for Precedence(P.tok) == prec {
+			pos, tok := P.pos, P.tok;
 			P.Next();
 			y := P.ParseBinaryExpr(nil, prec + 1);
+			
+			z := new(AST.Binary);
+			z.pos, z.tok, z.x, z.y = pos, tok, x, y;
+			x = z;
 		}
 	}
 	
@@ -753,7 +787,7 @@ func (P *Parser) ParseBinaryExpr(ident *AST.Ident, prec1 int) AST.Expr {
 
 
 // Expressions where the first token may be an identifier which has already been consumed.
-func (P *Parser) ParseIdentExpression(ident *AST.Ident) AST.Expr {
+func (P *Parser) ParseIdentExpression(ident *AST.Literal) AST.Expr {
 	P.Trace("IdentExpression");
 	indent := P.indent;
 	
@@ -773,6 +807,10 @@ func (P *Parser) ParseExpression() AST.Expr {
 	
 	x := P.ParseIdentExpression(nil);
 	
+	if !P.silent {
+		Printer.Print(x);
+	}
+
 	P.Ecart();
 	return x;
 }

usr/gri/pretty/pretty.go

@@ -13,7 +13,8 @@ import Printer "printer"
 
 
 var (
-    verbose = Flag.Bool("v", false, nil, "verbose mode");
+    silent = Flag.Bool("s", false, nil, "silent mode: no pretty print output");
+    verbose = Flag.Bool("v", false, nil, "verbose mode: trace parsing");
     sixg = Flag.Bool("6g", false, nil, "6g compatibility mode");
     tokenchan = Flag.Bool("token_chan", false, nil, "use token channel for scanner-parser connection");
 )
@@ -53,7 +54,7 @@ func main() {
 	    }
 
 	    parser := new(Parser.Parser);
-	    parser.Open(verbose.BVal(), scanner, tstream);
+	    parser.Open(silent.BVal(), verbose.BVal(), scanner, tstream);
 
 	    parser.ParseProgram();
 	}

usr/gri/pretty/printer.go

@@ -2,7 +2,64 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package Printer;
+package Printer
 
+import Scanner "scanner"
+import AST "ast"
 
-// TODO Fill in the code to print the AST
+
+type Printer struct {
+	
+}
+
+
+func (P *Printer) Print(s string) {
+	print(s);
+}
+
+
+func (P *Printer) PrintExpr(x AST.Expr) {
+/*
+	if x == nil {
+		P.Print("<nil>");
+		return;
+	}
+	
+	switch x.tok {
+	case Scanner.IDENT:
+		P.Print(x.val);
+	
+	case Scanner.INT, Scanner.FLOAT, Scanner.STRING:
+		P.Print(x.val);
+		
+	case Scanner.PERIOD:
+		P.PrintExpr(x.x);
+		P.Print(Scanner.TokenName(x.tok));
+		P.PrintExpr(x.y);
+
+	case Scanner.LBRACK:
+		P.PrintExpr(x.x);
+		P.Print("[");
+		P.PrintExpr(x.y);
+		P.Print("]");
+
+	default:
+		// unary or binary expression
+		print("(");
+		if x.x != nil {
+			P.PrintExpr(x.x);
+		}
+		P.Print(" " + Scanner.TokenName(x.tok) + " ");
+		P.PrintExpr(x.y);
+		print(")");
+	}
+*/
+}
+
+
+export func Print(x AST.Expr) {
+	var P Printer;
+	print("expr = ");
+	(&P).PrintExpr(x);
+	print("\n");
+}