Fixed special convertion case from decimal 'x.y()' to fraction

operator-fraction.go

@@ -94,6 +94,9 @@ func makeGeneratingFraction(s string) (f *fraction, err error) {
 	} else if s[0] == '+' {
 		s = s[1:]
 	}
+	if strings.HasSuffix(s, "()") {
+		s = s[0 : len(s)-2]
+	}
 	parts = strings.SplitN(s, ".", 2)
 	if num, err = strconv.ParseInt(parts[0], 10, 64); err != nil {
 		return

parser_test.go

@@ -158,6 +158,7 @@ func TestGeneralParser(t *testing.T) {
 		/* 137 */ {`builtin "os.file"`, int64(1), nil},
 		/* 138 */ {`v=10; v++; v`, int64(11), nil},
 		/* 139 */ {`1+1|2+0.5`, float64(2), nil},
+		/* 140 */ {`1.2()`, newFraction(6, 5), nil},
 	}
 
 	// t.Setenv("EXPR_PATH", ".")