checker/parser: check & gen stmts for ForIn & fix key, val vars

vlib/v/checker/checker.v

@@ -319,6 +319,11 @@ pub fn (c mut Checker) method_call_expr(method_call_expr mut ast.MethodCallExpr)
 		method_call_expr.return_type = method.return_type
 		return method.return_type
 	}
+	// TODO: str methods
+	if typ_sym.kind in [.map] && name == 'str' {
+		method_call_expr.return_type = table.string_type
+		return table.string_type
+	}
 	c.error('type `$typ_sym.name` has no method `$name`', method_call_expr.pos)
 	return table.void_type
 }
@@ -530,9 +535,7 @@ fn (c mut Checker) stmt(node ast.Stmt) {
 		ast.FnDecl {
 			c.expected_type = table.void_type
 			c.fn_return_type = it.return_type
-			for stmt in it.stmts {
-				c.stmt(stmt)
-			}
+			c.stmts(it.stmts)
 		}
 		ast.ForStmt {
 			typ := c.expr(it.cond)
@@ -541,22 +544,47 @@ fn (c mut Checker) stmt(node ast.Stmt) {
 			}
 			// TODO: update loop var type
 			// how does this work currenly?
-			for stmt in it.stmts {
-				c.stmt(stmt)
-			}
+			c.stmts(it.stmts)
 		}
 		ast.ForCStmt {
 			c.stmt(it.init)
 			c.expr(it.cond)
 			// c.stmt(it.inc)
 			c.expr(it.inc)
-			for stmt in it.stmts {
-				c.stmt(stmt)
-			}
+			c.stmts(it.stmts)
 		}
 		ast.ForInStmt {
-			c.expr(it.cond)
-			c.expr(it.high)
+			typ := c.expr(it.cond)
+			if it.is_range {
+				c.expr(it.high)
+			}
+			else {
+				mut scope := c.file.scope.innermost(it.pos.pos)
+				if it.key_var.len > 0 {
+					sym := c.table.get_type_symbol(typ)
+					key_type := match sym.kind {
+						.map{
+							sym.map_info().key_type
+						}
+						else {
+							table.int_type}
+	}
+					scope.override_var(ast.Var{
+						name: it.key_var
+						typ: key_type
+					})
+				}
+				value_type := c.table.value_type(typ)
+				if value_type == table.void_type {
+					typ_sym := c.table.get_type_symbol(typ)
+					c.error('for in: cannot index $typ_sym.name', it.pos)
+				}
+				scope.override_var(ast.Var{
+					name: it.val_var
+					typ: c.table.value_type(typ)
+				})
+			}
+			c.stmts(it.stmts)
 		}
 		// ast.GlobalDecl {}
 		// ast.HashStmt {}
@@ -566,9 +594,7 @@ fn (c mut Checker) stmt(node ast.Stmt) {
 		}
 		// ast.StructDecl {}
 		ast.UnsafeStmt {
-			for stmt in it.stmts {
-				c.stmt(stmt)
-			}
+			c.stmts(it.stmts)
 		}
 		else {}
 		// println('checker.stmt(): unhandled node')
@@ -761,6 +787,15 @@ pub fn (c mut Checker) ident(ident mut ast.Ident) table.Type {
 		if !name.contains('.') && !(c.file.mod.name in ['builtin', 'main']) {
 			name = '${c.file.mod.name}.$ident.name'
 		}
+		// hack - const until consts are fixed properly
+		if ident.name == 'v_modules_path' {
+			ident.name = name
+			ident.kind = .constant
+			ident.info = ast.IdentVar{
+				typ: table.string_type
+			}
+			return table.string_type
+		}
 		// constant
 		if constant := c.table.find_const(name) {
 			ident.name = name
@@ -913,30 +948,10 @@ pub fn (c mut Checker) index_expr(node mut ast.IndexExpr) table.Type {
 		else if typ_sym.kind == .map && table.type_idx(index_type) != table.string_type_idx {
 			c.error('non-string map index (type `$typ_sym.name`)', node.pos)
 		}
-		if typ_sym.kind == .array {
-			// Check index type
-			info := typ_sym.info as table.Array
-			return info.elem_type
+		value_type := c.table.value_type(typ)
+		if value_type != table.void_type {
+			return value_type
 		}
-		else if typ_sym.kind == .array_fixed {
-			info := typ_sym.info as table.ArrayFixed
-			return info.elem_type
-		}
-		else if typ_sym.kind == .map {
-			info := typ_sym.info as table.Map
-			return info.value_type
-		}
-		else if typ_sym.kind in [.byteptr, .string] {
-			return table.byte_type
-		}
-		else if table.type_is_ptr(typ) {
-			// byte* => byte
-			// bytes[0] is a byte, not byte*
-			return table.type_deref(typ)
-		}
-		// else {
-		// return table.int_type
-		// }
 	}
 	return typ
 }

vlib/v/gen/cgen.v

@@ -271,9 +271,7 @@ fn (g mut Gen) stmt(node ast.Stmt) {
 			// g.stmt(it.inc)
 			g.expr(it.inc)
 			g.writeln(') {')
-			for stmt in it.stmts {
-				g.stmt(stmt)
-			}
+			g.stmts(it.stmts)
 			g.writeln('}')
 		}
 		ast.ForInStmt {
@@ -284,7 +282,7 @@ fn (g mut Gen) stmt(node ast.Stmt) {
 				g.write('; $i < ')
 				g.expr(it.high)
 				g.writeln('; $i++) { ')
-				// g.stmts(it.stmts) TODO
+				g.stmts(it.stmts)
 				g.writeln('}')
 			}
 		}
@@ -297,9 +295,7 @@ fn (g mut Gen) stmt(node ast.Stmt) {
 				g.expr(it.cond)
 			}
 			g.writeln(') {')
-			for stmt in it.stmts {
-				g.stmt(stmt)
-			}
+			g.stmts(it.stmts)
 			g.writeln('}')
 		}
 		ast.GlobalDecl {

vlib/v/parser/parser.v

@@ -1096,13 +1096,14 @@ fn (p mut Parser) for_statement() ast.Stmt {
 	}
 	// `for i in vals`, `for i in start .. end`
 	else if p.peek_tok.kind in [.key_in, .comma] {
-		var_name := p.check_name()
-		mut val_name := ''
+		mut key_var_name := ''
+		mut val_var_name := p.check_name()
 		if p.tok.kind == .comma {
 			p.check(.comma)
-			val_name = p.check_name()
+			key_var_name = val_var_name
+			val_var_name = p.check_name()
 			p.scope.register_var(ast.Var{
-				name: val_name
+				name: key_var_name
 				typ: table.int_type
 			})
 		}
@@ -1118,13 +1119,17 @@ fn (p mut Parser) for_statement() ast.Stmt {
 			is_range = true
 			p.check(.dotdot)
 			high_expr = p.expr(0)
+			p.scope.register_var(ast.Var{
+				name: val_var_name
+				typ: table.int_type
+			})
+		}
+		else {
+			// this type will be set in checker
+			p.scope.register_var(ast.Var{
+				name: val_var_name
+			})
 		}
-		// TODO: update var type in checker
-		p.scope.register_var(ast.Var{
-			name: var_name
-			// expr: cond
-			
-		})
 		stmts := p.parse_block()
 		// println('nr stmts=$stmts.len')
 		p.close_scope()
@@ -1132,8 +1137,8 @@ fn (p mut Parser) for_statement() ast.Stmt {
 			stmts: stmts
 			pos: p.tok.position()
 			cond: cond
-			key_var: var_name
-			val_var: val_name
+			key_var: key_var_name
+			val_var: val_var_name
 			high: high_expr
 			is_range: is_range
 		}

vlib/v/table/table.v

@@ -29,19 +29,19 @@ pub:
 
 pub struct Arg {
 pub:
-	name        string
-	is_mut      bool
-	typ         Type
+	name   string
+	is_mut bool
+	typ    Type
 }
 
 pub struct Var {
 pub:
-	name        string
-	is_mut      bool
-	is_const    bool
-	is_global   bool
+	name      string
+	is_mut    bool
+	is_const  bool
+	is_global bool
 mut:
-	typ         Type
+	typ       Type
 }
 
 pub fn new_table() &Table {
@@ -411,6 +411,43 @@ pub fn (t mut Table) add_placeholder_type(name string) int {
 	return t.register_type_symbol(ph_type)
 }
 
+[inline]
+pub fn (t &Table) value_type(typ Type) Type {
+	typ_sym := t.get_type_symbol(typ)
+	if typ_sym.kind == .array {
+		// Check index type
+		info := typ_sym.info as Array
+		return info.elem_type
+	}
+	else if typ_sym.kind == .array_fixed {
+		info := typ_sym.info as ArrayFixed
+		return info.elem_type
+	}
+	else if typ_sym.kind == .map {
+		info := typ_sym.info as Map
+		return info.value_type
+	}
+	else if typ_sym.kind in [.byteptr, .string] {
+		return byte_type
+	}
+	else if type_is_ptr(typ) {
+		// byte* => byte
+		// bytes[0] is a byte, not byte*
+		return type_deref(typ)
+	}
+	else if type_is_variadic(typ) {
+		// ...string => string
+		return type_clear_extra(typ)
+	}
+	else {
+		// TODO: remove when map_string is removed
+		if typ_sym.name == 'map_string' {
+			return string_type
+		}
+		return void_type
+	}
+}
+
 pub fn (t &Table) check(got, expected Type) bool {
 	got_type_sym := t.get_type_symbol(got)
 	exp_type_sym := t.get_type_symbol(expected)