1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
|
//
// Copyright 2022 Sean C Foley
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package tree
// A PrefixLen indicates the length of the prefix for an address, section, division grouping, segment, or division.
// The zero value, which is nil, indicates that there is no prefix length.
type PrefixLen = *PrefixBitCount
// Len returns the length of the prefix. If the receiver is nil, representing the absence of a prefix length, returns 0.
// It will also return 0 if the receiver is a prefix with length of 0. To distinguish the two, compare the receiver with nil.
func (p *PrefixBitCount) Len() BitCount {
if p == nil {
return 0
}
return p.bitCount()
}
func (p *PrefixBitCount) bitCount() BitCount {
return BitCount(*p)
}
// A PrefixBitCount is the count of bits in a non-nil PrefixLen.
type PrefixBitCount uint8
// A BitCount represents a count of bits in an address, section, grouping, segment, or division.
// Using signed integers allows for easier arithmetic, avoiding bugs.
// However, all methods adjust bit counts to match address size,
// so negative bit counts or bit counts larger than address size are meaningless.
type BitCount = int // using signed integers allows for easier arithmetic
|
