parser: fix prefix precedence

vlib/builtin/int_test.v

@@ -29,6 +29,8 @@ fn test_float_equal_operator() {
 	assert a.gtbit(1)
 	assert a >= 1
 	assert a.gebit(1)
+	assert -1 == 1 * -1
+	assert -1.0 == 1.0 * -1.0
 
 	a = f64(1)
 	a += 0.000001

vlib/v/checker/checker.v

@@ -848,7 +848,7 @@ pub fn (c mut Checker) expr(node ast.Expr) table.Type {
 			type_sym := c.table.get_type_symbol(it.typ)
 			if expr_type_sym.kind == .sum_type {
 				info := expr_type_sym.info as table.SumType
-				if !it.typ in info.variants {
+				if !(it.typ in info.variants) {
 					c.error('cannot cast `$expr_type_sym.name` to `$type_sym.name`', it.pos)
 					// c.error('only $info.variants can be casted to `$typ`', it.pos)
 				}

vlib/v/gen/cgen.v

@@ -840,9 +840,9 @@ fn (g mut Gen) gen_fn_decl(it ast.FnDecl) {
 				g.writeln('free(_const_os__args.data); // empty, inited in _vinit()')
 			}
 			if g.pref.os == .windows {
-				g.writeln('_const_os__args = os__init_os_args_wide(___argc, ___argv);')
+				g.writeln('\t_const_os__args = os__init_os_args_wide(___argc, ___argv);')
 			} else {
-				g.writeln('_const_os__args = os__init_os_args(___argc, (byteptr*)___argv);')
+				g.writeln('\t_const_os__args = os__init_os_args(___argc, (byteptr*)___argv);')
 			}
 		}
 	}
@@ -1123,7 +1123,9 @@ fn (g mut Gen) expr(node ast.Expr) {
 			}
 			// g.write('/*pref*/')
 			g.write(it.op.str())
+			//g.write('(')
 			g.expr(it.right)
+			//g.write(')')
 			g.is_amp = false
 		}
 		ast.SizeOf {
@@ -1390,7 +1392,8 @@ fn (g mut Gen) infix_expr(node ast.InfixExpr) {
 			g.expr(node.right)
 			g.write('), $tmp, $elem_type_str)')
 		}
-	} else if (node.left_type == node.right_type ) && node.left_type in [ table.f32_type_idx, table.f64_type_idx ] && node.op in [ .eq, .ne ] {
+	} else if (node.left_type == node.right_type) && node.left_type in [table.f32_type_idx,
+		table.f64_type_idx] && node.op in [.eq, .ne] {
 		// floats should be compared with epsilon
 		if node.left_type == table.f64_type_idx {
 			if node.op == .eq {
@@ -1398,7 +1401,7 @@ fn (g mut Gen) infix_expr(node ast.InfixExpr) {
 			} else {
 				g.write('f64_ne(')
 			}
-		}else{
+		} else {
 			if node.op == .eq {
 				g.write('f32_eq(')
 			} else {

vlib/v/parser/parser.v

@@ -863,7 +863,7 @@ fn (p mut Parser) prefix_expr() ast.PrefixExpr {
 		p.is_amp = true
 	}
 	p.next()
-	right := p.expr(1)
+	right := p.expr(token.Precedence.prefix)
 	p.is_amp = false
 	return ast.PrefixExpr{
 		op: op

vlib/v/token/token.v

@@ -303,7 +303,7 @@ pub enum Precedence {
 	product // * or /
 	// mod // %
 	prefix // -X or !X
-	postfix
+	postfix // ++ or --
 	call // func(X) or foo.method(X)
 	index // array[index], map[key]
 }