ast: return types, variable declaration

vlib/compiler/expression.v

@@ -4,8 +4,9 @@
 module compiler
 
 fn (p mut Parser) bool_expression() string {
+	is_ret := p.prev_tok == .key_return
 	start_ph := p.cgen.add_placeholder()
-	expected := p.expected_type
+	mut expected := p.expected_type
 	tok := p.tok
 	typ := p.bterm()
 	mut got_and := false // to catch `a && b || c` in one expression without ()
@@ -46,7 +47,11 @@ fn (p mut Parser) bool_expression() string {
 		println(tok.str())
 		p.error('expr() returns empty type')
 	}
+	if p.inside_return_expr { //is_ret { // return a,b hack TODO
+		expected = p.expected_type
+	}
 	if expected != typ && expected in p.table.sum_types { // TODO perf
+	//p.warn('SUM CAST exp=$expected typ=$typ p.exp=$p.expected_type')
 		p.cgen.set_placeholder(start_ph,
 			//'/*SUM TYPE CAST*/($expected) { .obj = &($typ[]) { ')
 			'/*SUM TYPE CAST*/($expected) { .obj = memdup(& ')

vlib/compiler/vfmt.v

@@ -272,8 +272,9 @@ fn (p &Parser) gen_fmt() {
 	s3 := s2.replace(') or{', ') or {')
 	s4 := s3.replace(')or{', ') or {')
 	s5 := s4.replace('or{', 'or {')
+	s6 := s5.replace('}}\n', '}\n\t}\n')
 
-	s := s5
+	s := s6
 
 	if s == '' {
 		return

vlib/compiler2/ast/ast.v

@@ -11,8 +11,9 @@ import (
 struct Foo {}
 
 pub type Expr = Foo | IfExpr | BinaryExpr | UnaryExpr |
-	StringLiteral  | IntegerLiteral
-pub type Stmt = Foo | VarDecl
+	StringLiteral  | IntegerLiteral | VarDecl
+
+pub type Stmt = Foo | Foo //VarDecl
 
 pub struct IntegerLiteral {
 pub:
@@ -43,6 +44,7 @@ pub struct VarDecl {
 pub:
 	name string
 	expr Expr
+	typ Type
 
 }
 
@@ -51,6 +53,18 @@ pub:
 	exprs []Expr
 }
 
+pub struct Type {
+pub:
+	name string
+}
+
+pub const (
+	string_type = Type{'string'}
+	int_type = Type{'int'}
+	void_type = Type{'void'}
+)
+
+
 // A single identifier
 struct Ident {
 	token token.Token
@@ -63,7 +77,9 @@ pub:
 	//op    BinaryOp
 	op    token.Token
 	left  Expr
+	left_type Type
 	right Expr
+	right_type Type
 }
 
 pub struct UnaryExpr {
@@ -92,11 +108,14 @@ pub fn (x Expr) str() string {
 		BinaryExpr {
 			return '(${it.left.str()} $it.op.str() ${it.right.str()})'
 		}
-		//ScalarExpr {
-			//return '${it.left.str()}$it.val'
-		//}
 		UnaryExpr {
-			return '${it.left.str()}$it.op.str()'
+			return it.left.str() + it.op.str()
+		}
+		IntegerLiteral {
+			return it.val.str()
+		}
+		IntegerLiteral {
+			return '"$it.val"'
 		}
 		else { return '' }
 	}

vlib/compiler2/cgen/cgen.v

@@ -41,12 +41,11 @@ const (
 	void_type = Type{'void'}
 )
 
-fn (g mut Gen) expr(node ast.Expr) Type {
+fn (g mut Gen) expr(node ast.Expr) {
 	//println('cgen expr()')
 	match node {
 		ast.IntegerLiteral {
 			g.write(it.val.str())
-			return int_type
 		}
 		ast.UnaryExpr {
 			g.expr(it.left)
@@ -54,10 +53,9 @@ fn (g mut Gen) expr(node ast.Expr) Type {
 		}
 		ast.StringLiteral {
 			g.write('"$it.val"')
-			return string_type
 		}
 		ast.BinaryExpr {
-			typ := g.expr(it.left)
+			g.expr(it.left)
 			match it.op {
 				.plus {	g.write(' + ')	}
 				.minus {	g.write(' - ')	}
@@ -65,22 +63,24 @@ fn (g mut Gen) expr(node ast.Expr) Type {
 				.div {	g.write(' / ')	}
 				else {}
 			}
-			typ2 := g.expr(it.right)
-			if typ.name != typ2.name {
-				println('bad types $typ.name $typ2.name')
-			}
-			return typ
+			g.expr(it.right)
+		//	if typ.name != typ2.name {
+				//verror('bad types $typ.name $typ2.name')
+			//}
 		}
 		ast.VarDecl {
-			g.write('var $it.name = ')
+			g.write('$it.typ.name $it.name = ')
 			g.expr(it.expr)
 			g.writeln(';')
-			return void_type
 		}
 		else {
 			println('bad node')
 		}
 	}
-	return void_type
+}
+
+fn verror(s string) {
+	println(s)
+	exit(1)
 }
 

vlib/compiler2/parser/parser.v

@@ -7,6 +7,7 @@ import (
 	compiler2.scanner
 	compiler2.ast
 	compiler2.token
+	compiler2.table
 )
 
 struct Parser {
@@ -14,20 +15,49 @@ struct Parser {
 mut:
 	tok     token.Token
 	lit     string
+	//vars []string
+	table &table.Table
 }
 
-pub fn parse_expr(text string) ast.Expr {
+pub fn parse_expr(text string, table &table.Table) ast.Expr {
 	mut s := scanner.new_scanner(text)
 	res := s.scan()
 	mut p := Parser{
 		scanner: s
 		tok: res.tok
 		lit: res.lit
+		table: table
 	}
-	// return p.expr()
-	return p.expr(token.lowest_prec)
+	expr,_ := p.expr(token.lowest_prec)
+	return expr
 }
 
+pub fn parse_file(text string, table &table.Table) ast.Program {
+	s := scanner.new_scanner(text)
+	mut exprs := []ast.Expr
+	mut p := Parser{
+		scanner: s
+		//tok: res.tok
+		//lit: res.lit
+		table: table
+	}
+	p.next()
+	for {
+		//res := s.scan()
+		if p.tok == .eof {
+			break
+		}
+		println('expr at ' + p.tok.str())
+		expr,_ := p.expr(token.lowest_prec)
+		exprs << expr
+		p.next()
+	}
+	println('nr exprs = $exprs.len')
+	println(exprs[0])
+	return ast.Program{exprs}
+}
+
+/*
 pub fn parse_stmt(text string) ast.Stmt {
 	mut s := scanner.new_scanner(text)
 	res := s.scan()
@@ -38,6 +68,8 @@ pub fn parse_stmt(text string) ast.Stmt {
 	}
 	return p.stmt()
 }
+*/
+
 
 fn (p mut Parser) next() {
 	res := p.scanner.scan()
@@ -47,15 +79,40 @@ fn (p mut Parser) next() {
 }
 
 // Implementation of Pratt Precedence
-pub fn (p mut Parser) expr(rbp int) ast.Expr {
+pub fn (p mut Parser) expr(rbp int) (ast.Expr,ast.Type) {
 	// null denotation (prefix)
 	tok := p.tok
 	lit := p.lit
+
+	if p.tok == .name {
+		name := p.lit
+		p.next()
+		if p.tok == .decl_assign {
 			p.next()
 			mut node := ast.Expr{}
+			expr,t :=p.expr(token.lowest_prec)
+			if name in p.table.names {
+				verror('redefinition of `$name`')
+			}
+			p.table.names << name
+			println(p.table.names)
+			println('added $name')
+			// TODO can't return VarDecl{}
+			node = ast.VarDecl{
+				name: name
+				expr: expr//p.expr(token.lowest_prec)
+				typ: t
+			}//, ast.void_type
+			return node, ast.void_type
+		}
+	} else {
+		p.next()
+	}
+	mut node := ast.Expr{}
+	mut typ := ast.void_type
 	match tok {
 		.lpar {
-			node = p.expr(0)
+			node,typ = p.expr(0)
 			if p.tok != .rpar {
 				panic('Parse Error: expected )')
 			}
@@ -68,45 +125,67 @@ pub fn (p mut Parser) expr(rbp int) ast.Expr {
 					node = ast.StringLiteral{
 						val: lit
 					}
-				}	if tok == .number {
+					typ = ast.string_type
+				}
+				if tok == .number {
 					node = ast.IntegerLiteral{
 						val: lit.int()
 					}
+					typ = ast.int_type
 				}
 				// else {
 				// verror('bad scalar token')
 				// }
 			}
 			if !tok.is_scalar() && tok.is_unary() {
+				expr,_ := p.expr(token.highest_prec)
 				node = ast.UnaryExpr{
-					left: p.expr(token.highest_prec)
+					// left: p.expr(token.highest_prec)
+					left: expr
 					op: tok
 				}
 			}
-		}}
+		}
+	}
 	// left binding power
 	for rbp < p.tok.precedence() {
 		tok2 := p.tok
 		p.next()
+		//mut t1 := ast.Type{}
+		mut t2 := ast.Type{}
+		//mut q := false
 		// left denotation (infix)
 		if tok2.is_right_assoc() {
+			//q = true
+			mut expr := ast.Expr{}
+			expr,t2 = p.expr(tok2.precedence() - 1)
 			node = ast.BinaryExpr{
 				left: node
+				//left_type: t1
 				op: tok2
-				right: p.expr(tok2.precedence() - 1)
+				// right: p.expr(tok2.precedence() - 1)
+
+				right: expr
+
+			}
+			if typ.name != t2.name {
+				println('bad types $typ.name $t2.name')
 			}
 		}
 		if !tok2.is_right_assoc() && tok2.is_left_assoc() {
+			mut expr := ast.Expr{}
+			expr,t2 = p.expr(tok2.precedence())
 			node = ast.BinaryExpr{
 				left: node
 				op: tok2
-				right: p.expr(tok2.precedence())
+				right: expr
 			}
 		}
 	}
-	return node
+	return node,typ
 }
 
+/*
 fn (p mut Parser) stmt() ast.Stmt {
 	if p.tok == .name {
 		name := p.lit
@@ -131,6 +210,8 @@ fn (p mut Parser) stmt() ast.Stmt {
 
 	return ast.VarDecl{}
 }
+*/
+
 
 fn verror(s string) {
 	println(s)

vlib/compiler2/parser/parser_test.v

@@ -3,6 +3,8 @@ module parser
 import (
 	compiler2.ast
 	compiler2.cgen
+	compiler2.table
+
 )
 
 fn test_parser() {
@@ -11,8 +13,8 @@ fn test_parser() {
 	//expr := ast.BinaryExpr{}
 
 	// print using walk
-	expr := parse_expr('3 + 7')
-	println('\n')
+	//expr := parse_expr('3 + 7')
+	//println('\n')
 
 	text_expr := [
 		'1 += 2',
@@ -24,29 +26,53 @@ fn test_parser() {
 		'2 ^ 8 * (7 * 6)',
 		'20 + (10 * 15) / 5', // 50
 		'(2) + (17*2-30) * (5)+2 - (8/2)*4', // 8
-		'2 + "hi"'
+		'2 + "hi"',
+		'x := 10'
 	]
 
+	table := &table.Table{}
 	for s in text_expr {
 		// print using str method
-		x := parse_expr(s)
+		x := parse_expr(s, table)
 		println('source: $s')
 		println('parsed: $x')
 		println('===================')
 	}
 }
+/*
+fn test_cgen2() {
+	s := '2 + 3
+	5+7
+//x := 100
+'
+	table := &table.Table{}
+	prog := parse_file(s, table)
+	cgen.gen(prog)
+	println('done')
+}
+*/
 
 
 fn test_cgen() {
+	//if true { return }
+	s := [
+		'x := 10',
+		//'x := 10'
+	]
 	//expr := parse_expr('3 + 7 * 2')
 	//expr2 := parse_stmt('a := 3 + "f"')
-	expr2 := parse_expr('2 + "helo"')
-	program := ast.Program{
-		exprs: [
-			expr2,
+	mut e := []ast.Expr
+	table := &table.Table{}
+	for ss in s {
+	//expr2 := parse_expr('x := 10')
+	//program := ast.Program{
+		e << parse_expr(ss, table)
+		//exprs: [
+			//expr2,
 			//parse_expr('2 * 2'),
-		]
+		//]
 	}
+	program := ast.Program{exprs:e}
 	cgen.gen(program)
 	//cgen.save()
 }

vlib/compiler2/table/table.v

@@ -0,0 +1,7 @@
+module table
+
+pub struct Table {
+pub mut:
+	names []string
+
+}

vlib/compiler2/token/token.v

@@ -289,7 +289,7 @@ fn (t []Token) contains(val Token) bool {
 pub fn (t Token) str() string {
 	lit := 't.lit'
 	if t == .number {
-		return lit
+		return 'number'
 	}
 	if t == .chartoken {
 		return '`lit`'