parser: fix `a & b == c` precedence

vlib/builtin/int_test.v

@@ -66,6 +66,15 @@ fn test_str_methods() {
 	assert u64(-1).str() == '18446744073709551615'
 }
 
+fn test_and() {
+	c:=[1,2,3,4,5]
+	assert c[0] & 1 != 0
+	assert c[1] & 1 == 0
+	assert c[2] & 1 != 0
+	assert c[3] & 1 == 0
+	assert c[4] & 1 != 0
+}
+
 /*
 fn test_cmp() {
 	assert 1 ≠ 2

vlib/compiler/expression.v

@@ -473,14 +473,22 @@ fn (p mut Parser) expression() string {
 			p.error('strings only support `+` operator')
 		}
 		expr_type := p.term()
-		if (tok_op in [.pipe, .amp, .xor]) && !(is_integer_type(expr_type) &&
+		mut open := false
-			is_integer_type(typ)) {
+		if tok_op in [.pipe, .amp, .xor] {
+			if  !(is_integer_type(expr_type) &&			is_integer_type(typ)) {
 				p.error('operator ${tok_op.str()} is defined only on integer types')
 			}
+			p.cgen.set_placeholder(ph, '(')
+			open = true
+		}
 		p.check_types(expr_type, typ)
 		if (is_str || is_ustr) && tok_op == .plus && !p.is_js {
 			p.gen(')')
 		}
+		if open {
+			p.gen(')')
+
+		}
 		// Make sure operators are used with correct types
 		if !p.pref.translated && !is_str && !is_ustr && !is_num {
 			T := p.table.find_type(typ)