37 lines
1.1 KiB
Go
37 lines
1.1 KiB
Go
// Copyright 2015 The Go Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
package precis
|
|
|
|
import (
|
|
"unicode/utf8"
|
|
)
|
|
|
|
// TODO: Add contextual character rules from Appendix A of RFC5892.
|
|
|
|
// A class is a set of characters that match certain derived properties. The
|
|
// PRECIS framework defines two classes: The Freeform class and the Identifier
|
|
// class. The freeform class should be used for profiles where expressiveness is
|
|
// prioritized over safety such as nicknames or passwords. The identifier class
|
|
// should be used for profiles where safety is the first priority such as
|
|
// addressable network labels and usernames.
|
|
type class struct {
|
|
validFrom property
|
|
}
|
|
|
|
// Contains satisfies the runes.Set interface and returns whether the given rune
|
|
// is a member of the class.
|
|
func (c class) Contains(r rune) bool {
|
|
b := make([]byte, 4)
|
|
n := utf8.EncodeRune(b, r)
|
|
|
|
trieval, _ := dpTrie.lookup(b[:n])
|
|
return c.validFrom <= property(trieval)
|
|
}
|
|
|
|
var (
|
|
identifier = &class{validFrom: pValid}
|
|
freeform = &class{validFrom: idDisOrFreePVal}
|
|
)
|