diff --git a/vlib/v/ast/ast.v b/vlib/v/ast/ast.v
index 5ba2140eb2..7ce5e9f4d6 100644
--- a/vlib/v/ast/ast.v
+++ b/vlib/v/ast/ast.v
@@ -128,7 +128,6 @@ pub:
 
 pub struct Arg {
 pub:
-	
 	name   string
 	is_mut bool
 	typ    table.Type
@@ -463,9 +462,9 @@ pub:
 
 pub struct FnTypeDecl {
 pub:
-	name    string
-	is_pub  bool
-	typ     table.Type
+	name   string
+	is_pub bool
+	typ    table.Type
 }
 
 pub struct DeferStmt {
@@ -535,10 +534,12 @@ pub:
 
 pub struct CastExpr {
 pub:
-	typ     table.Type
-	expr    Expr // `buf`
-	arg     Expr // `n` in `string(buf, n)`
-	has_arg bool
+	expr      Expr // `buf`
+	arg       Expr // `n` in `string(buf, n)`
+	typ       table.Type // `string`
+mut:
+	expr_type table.Type // `byteptr`
+	has_arg   bool
 }
 
 pub struct AssertStmt {
diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index d96eebf273..99033a1970 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -290,17 +290,17 @@ pub fn (c mut Checker) method_call_expr(method_call_expr mut ast.MethodCallExpr)
 		return info.elem_type
 	}
 	if method := c.table.type_find_method(typ_sym, name) {
-		if method_call_expr.args.len < method.args.len-1 {
+		if method_call_expr.args.len < method.args.len - 1 {
 			c.error('too few arguments in call to `${typ_sym.name}.$name`', method_call_expr.pos)
 		}
-		else if !method.is_variadic && method_call_expr.args.len > method.args.len+1 {
+		else if !method.is_variadic && method_call_expr.args.len > method.args.len + 1 {
 			c.error('too many arguments in call to `${typ_sym.name}.$name` ($method_call_expr.args.len instead of $method.args.len)', method_call_expr.pos)
 		}
 		// if name == 'clone' {
 		// println('CLONE nr args=$method.args.len')
 		// }
 		for i, arg_expr in method_call_expr.args {
-			c.expected_type = method.args[i+1].typ
+			c.expected_type = method.args[i + 1].typ
 			c.expr(arg_expr)
 		}
 		method_call_expr.receiver_type = method.args[0].typ
@@ -536,7 +536,10 @@ fn (c mut Checker) stmt(node ast.Stmt) {
 				c.stmt(stmt)
 			}
 		}
-		// ast.ForInStmt {}
+		ast.ForInStmt {
+			c.expr(it.cond)
+			c.expr(it.high)
+		}
 		// ast.GlobalDecl {}
 		// ast.HashStmt {}
 		ast.Import {}
@@ -584,7 +587,7 @@ pub fn (c mut Checker) expr(node ast.Expr) table.Type {
 			return table.bool_type
 		}
 		ast.CastExpr {
-			c.expr(it.expr)
+			it.expr_type = c.expr(it.expr)
 			if it.has_arg {
 				c.expr(it.arg)
 			}
@@ -739,7 +742,7 @@ pub fn (c mut Checker) ident(ident mut ast.Ident) table.Type {
 		// Function object (not a call), e.g. `onclick(my_click)`
 		if func := c.table.find_fn(name) {
 			fn_type := c.table.find_or_register_fn_type(func)
-			ident.name = name			
+			ident.name = name
 			ident.kind = .function
 			ident.info = ast.IdentFn{
 				typ: fn_type
diff --git a/vlib/v/gen/cgen.v b/vlib/v/gen/cgen.v
index 3c7bbaf743..1bcc65e4a3 100644
--- a/vlib/v/gen/cgen.v
+++ b/vlib/v/gen/cgen.v
@@ -494,7 +494,7 @@ fn (g mut Gen) expr(node ast.Expr) {
 				g.out.go_back(1)
 			}
 			if it.typ == table.string_type_idx {
-				// tos(str, len), tos2(str)
+				// `tos(str, len)`, `tos2(str)`
 				if it.has_arg {
 					g.write('tos(')
 				}
@@ -502,8 +502,14 @@ fn (g mut Gen) expr(node ast.Expr) {
 					g.write('tos2(')
 				}
 				g.expr(it.expr)
+				sym := g.table.get_type_symbol(it.expr_type)
+				if sym.kind == .array {
+					// if we are casting an array, we need to add `.data`
+					g.write('.data')
+				}
 				if it.has_arg {
-					g.write(',')
+					// len argument
+					g.write(', ')
 					g.expr(it.arg)
 				}
 				g.write(')')
diff --git a/vlib/v/table/atype_symbols.v b/vlib/v/table/atype_symbols.v
index 46d617c00d..8901646f8b 100644
--- a/vlib/v/table/atype_symbols.v
+++ b/vlib/v/table/atype_symbols.v
@@ -7,7 +7,7 @@ import (
 	strings
 )
 
-pub type TypeInfo = Array | ArrayFixed | Map | Struct |
+pub type TypeInfo = Array | ArrayFixed | Map | Struct | 	
 MultiReturn | Alias | Enum | SumType | Fn
 
 pub struct TypeSymbol {
@@ -355,8 +355,7 @@ pub fn (k Kind) str() string {
 			'enum'
 		}
 		else {
-			'unknown'
-		}
+			'unknown'}
 	}
 	return k_str
 }
@@ -434,7 +433,6 @@ pub fn (table &Table) type_to_str(t Type) string {
 		res += ')'
 		return res
 	}
-
 	mut res := sym.name
 	if sym.kind == .array {
 		res = res.replace('array_', '[]')
diff --git a/vlib/v/table/table.v b/vlib/v/table/table.v
index 35b04b4bd4..23fc788749 100644
--- a/vlib/v/table/table.v
+++ b/vlib/v/table/table.v
@@ -67,11 +67,11 @@ pub fn (f &Fn) signature() string {
 		// TODO: for now ignore mut/pts in sig for now
 		typ := type_set_nr_muls(arg.typ, 0)
 		// if arg.is_mut {
-		// 	sig += 'mut_'
+		// sig += 'mut_'
 		// }
 		// sig += '$arg.typ'
 		sig += '$typ'
-		if i < f.args.len-1 {
+		if i < f.args.len - 1 {
 			sig += '_'
 		}
 	}
@@ -294,7 +294,9 @@ pub fn (t &Table) array_fixed_name(elem_type Type, size int, nr_dims int) string
 pub fn (t &Table) map_name(key_type Type, value_type Type) string {
 	key_type_sym := t.get_type_symbol(key_type)
 	value_type_sym := t.get_type_symbol(value_type)
-	return 'map_${key_type_sym.name}_${value_type_sym.name}' + if type_is_ptr(value_type) { '_ptr' } else { '' }
+	suffix := if type_is_ptr(value_type) { '_ptr' } else { '' }
+	return 'map_${key_type_sym.name}_${value_type_sym.name}' + suffix
+	// return 'map_${value_type_sym.name}' + suffix
 }
 
 pub fn (t mut Table) find_or_register_map(key_type, value_type Type) int {
@@ -380,12 +382,7 @@ pub fn (t mut Table) find_or_register_multi_return(mr_typs []Type) int {
 }
 
 pub fn (t mut Table) find_or_register_fn_type(f Fn) int {
-	name := if f.name.len > 0 {
-		f.name
-	}
-	else {
-		'anon_$f.signature()'
-	}
+	name := if f.name.len > 0 { f.name } else { 'anon_$f.signature()' }
 	return t.register_type_symbol(TypeSymbol{
 		kind: .function
 		name: name